In high school, I struggled like crazy because all my science / maths teachers were either incompetent, or just in their own bubble. I was lucky that in Uni, to enjoy the teachings of great professors that really loved their job and cared about their students. These have been my role models, and now., that I am much older and wiser, I give back... especially at the level where there is the biggest lack of good teachers.
“First, a dielectric lets the effect of a charge (the electric field it generates) pass through it, not the charge itself.” What do you think of an alternative view? a dielectric lets an electromotive force to push / build charge in it and not through it.
I had to review math by myself at 40, and now I understand derivatives and integrals. Teachers were just bad in the late 90s/early 2000... I didn't understand a thing back then!@@PhysicsMadeEasy
This is another great video. The analogy with mechanical energy stored in a spring at the end really does add a tangible image that pulls it all together. The meaning of equations, even simple ones, can be quite elusive.
Yes, that is why I made this analogy... Many find these equations quite abstract, the analogy allows to make it more concrete. What you can try is look at other equations, and try to find a tangible picture for these two. Feynman does this a lot, that's why he is a great teacher. For example, I really enjoyed his analogy between RLC circuits and a damped mechanical oscillator (his lessons are downloadable for free online as text).
So, im translating everything to field theory terms in my head, but man you helped so many things click for me. Its very difficult to find such a full description on this subject
Thank you so much for this video - very clear, particularly appreciate correct closed captioning added by you! automatic is so unreliable. hugely appreciated.
Thank you so much Cerys! Your comment is very much appreciated, because to be honest, it is quite a lengthy process to write these directly in the editing software. But it is a step I always do before the final rendering: I know that if I were a viewer of the channel, I would appreciate this: The subtitles in TH-cam are not always accurate, hide too much space of the screen and are really not aesthetic!
Hello Marwa, I am super happy to read this. This is exactly why I make these videos: to simplify student's life, so they get a conceptual understanding and then dig deeper in their teacher's or professor's lecture with improved confidence!
I kept thinking "dielectric" must have two of something, like "dipole". Until this video, I didn't know it meant going through something, "dia" as in "diagram". Thank you for pointing that out. Good video.
Cheers William. same here, when I was a student I associated the di to 2, like in dipole... I suppose many students do the same faulty association... I thought it was important to do this little etymology section to put things straight! My assumption was therefore right: I am glad I clarified this for you.
I watched your video for the first time and within 2 mins of watching I subscribed to your channel. Thankyou so much for clearing the concepts so well.
It was an excellent explanation, I learned so much from it. It is wonderful to learn from teachers who can explain things this clearly and tangibly, which also shows their profound grasp on the subject and it really translates to students. Merci beaucoup Professeur !
@@PhysicsMadeEasySir Your explanation is really very effective. Please try to make videos on other physical quantities too.. Mind me If you think that it takes a lot of time to edit them or whatever, your makingtheconceptsclear quality will be as effective on a simple white board too..
Physics and Music are deeply entertwined! I am actually a musician myself, and earn a fraction of my living from he royalties of my music work. When I used to teach face to face, I would invite my physics students to the studio and show them how various sounds could be made by interference of various sinewaves (in other words, sound design using a synth).
"Electromagnetic Fields & Waves" (3rd ed.) by Lorrain & Corson covers dielectrics in Chs. 9 & 10. I used the 2nd edition as an Undergrad back in the day.
Hello Sir! This is the best physics channel that I have come across so far❤...and this channel is perfect for physics lovers like us😊😊...This was the kind of channel that I was looking for a very long time!!! ❤❤.. Physics is a fundamental part of our life.. It is something that we can observe, analyse, and experiment to study details of nature...we should enjoy learning like the way you're teaching....Excellent explanation!!!!... Looking forward to more videos on particle physics, light energy, high energy physics, and many more❤❤❤
Hi Swarali. Thank you so much for your very kind words, and pointing out our common passion! Thank you also for your suggestions of new videos. You seem to enjoy particle physics: maybe you have seen that I made some time ago a playlist on the subject. Feel free to visit it (th-cam.com/video/gy-durcAhJ4/w-d-xo.html)
Bonjour (hi) sir.. I have doubt in dipole moment..... That dipole moment will happen when electric field passed through it ????? Is it right????? Could you pls reply...sir...
Dipole moments do not necessarily need an external field to exist. For example, a water molecule is polar by structure. In a glass of water, the molecules are oriented randomly so there is no net dipole moment for the glass of water. However, applying an electric field will orient all the dipole moments of the water molecules generatiing a net electric dipole for the glass of water But applying a field , one can also create electric dipole moments in a medium composed of positive and negative charges that are uniformly dispersed. In that case, you can get also a net electric dipole moment. I recommend you check my video on magnetic dipole moments, it could help: th-cam.com/video/lG1TP5-rKfM/w-d-xo.htmlsi=7wEytIHJeieiQggR
You are warmly welcome. That's why i am here: to debunk the basics, so that when you go back to your class notes, you see the light :-)! Thank you for letting me know, it really encourages me.
@@PhysicsMadeEasy ofcourse I see the light! But I am A communication engineer now. N.B I didn't wrote this comment for only this video, but also for all of your videos. I have watched most of your videos and I have answered my all doubts. Again I want to say you Keep it up...and Make the illusion to be clear. You are the light to see all technology and physics. THAK YOU!!!👍👍❤
Hi Abdulraheem, unfortunately, not really. Still, the lessons that I found the most inspiring , and that I use when I have a doubt are the lectures of Richard Feynman. These are free on the web to download. But these are also very dense (every word counts), and you need a at least an undergraduate math background to fully understand the content. I hope this helps!
at 6:55 assuming epsilon approaches to infinity, E' goes to E, Er(=D displacement field) disappears, but when epsilon approaches to infinity and still finite, Er(=D) still goes to zero, while E'(=P due to polarization) approaches to infinity, i found this contradiction in EM theory. how high can an epsilon go without being broken away to be free? even if they are free, but the bulk of the left free MUST be equal to the bulk of the right "HOLES" that which should be considered the macroscopic polarization..... fine fine E can be discontinuous but must be conservative without changing B field present.
I am not fully sure I understand your comment (I feel there is an interrogation behind it that I do not see clearly). What I know is that permittivity cannot be infinite in the real world... It is a property that depends on the charge structure of a material. In any material, there will always be a limit to how much it can get polarised. Without limit, it would not be a dielectric anymore, because there would not be any polarisation but a current flow.... If you wish to consider epsilon as infinite: that means there is a current instead of a polarisation... It's not a dielectric anymore but a conductor or a superconductor. If you wish to say it tends to infinity (without reaching it), you are inventing a theoretical material... Maybe you can find an answer to your question by checking out more in detail ferroelectric materials, these tend to have very high permittivities, and then extrapolate from there.. My answer was probably not very helpful here, but maybe it gave you a lead to investigate further.
@@PhysicsMadeEasy i think my confusion came from here, the higher epsilon the better the capacity is in formula, so why not using salt water ( epsilon=80~88 instead of paper or plastic) but salt water conducts electricity. and when epsilon goes to infinity, the material goes to be like a conductor. the higher the epsilon meaning E (external E) is NOT passing through well, but P(polarization or induced E) will rise and store more energy into the material, so dielectric permittivity(electric field passing through) should take the max value for air and min value for matal. but they are apposite, min value for air , max for metal. why or how?
@@abcdef2069 Let’s go back to the definition of permittivity : It is the ability of a material to resist the formation of an electric field inside it. Metals are conductors, so as soon as you try to apply an electric field on it, the electrons in the metal are going to move along the field lines until they find equilibrium: When they finally do, there is now in the metal an electric field that cancels the applied field. So there is no resultant field in the metal. That’s why the permittivity is theoretically infinite for a metal. Finding an infinity, is very often a sign that there is something wrong with the reasoning: And what is wrong here is to assume that a metal is a dielectric … It’s a little like if you were measuring the hardness of a liquid… A liquid is not a solid. I hope this idea helps.
Amazing!!! Your Videos enhances way of thinking.. Keep it up Sir! Our prof. also explained (Why capacitance increases due to dielectric) by breakdown voltage concept also..
Thank you Parmanand. Breakdown Voltage is more related to when the voltage, thus the field is so large that it can modify the electronic structure of the material. Basically the electric force becomes large enough to strip atoms / molecules of some of their electrons. This usually results in damaging irreversibly the capacitor.
Sir by Gauss theorem , electric field between two opposite charges is the sum of electric field of both charges and resultant has more magnitude than electric field exerted by them individually . Then how can resultant electric potential gets decreased when the relation |E| = |dv/dr| shows that they are directly proportional to each other . Hope you would reply. Yours sincerely Talmeez Abbas
Hello Talmeez, you wrote: "Sir by Gauss theorem , electric field between two opposite charges is the sum of electric field of both charges and resultant has more magnitude than electric field exerted by them individually ." Be careful. you should have said: "the vector sum". If you consider a point between the two positive charges, the resultant electric field strength at that point being the vector sum, its magnitude will be less than the individual electric field strengths. Can you reformulate your question regarding E=dv/dr? E is not proportional to v, it is it derivative in regards to space...
Hi @Physics Made Easy I find your videos both inspiring and educational, yet I feel the playlist on electricity went a little too off on the advanced side not explaining the basics thoroughly enough. Would you ever consider adding a few detailed videos on resistance, voltage, current, and basic circuits? Thank you
Hello James, thank you for your encouragement. There is no real structure or plan in the playlists (playlists are not courses), I just categorize the videos in major subjects. Still, when thinking of it, what you say is correct. Recently, I did tend to make videos about the topics I find inspiring, and thus, that can be of higher level (yet remaining within the scope of high school physics). Your suggestion remains excellent though. thanks. I will consider this for future videos. Note that some of the older videos on that playlist do talk about circuit basics, but in a more applied and concise way.
Hlo Sir, How come the position and momentum are independent variables in Hamiltonian mechanics? Consider SHM Hamiltonian when we change position , Momentum changes right? Both are related to each other right? Thank you
Hi Gowri, I see with that question that you stepped your level a notch in physics. Like my real life students, my TH-cam students are growing up lol! It's so cute haha ;-) I am more familiar with Lagrangian mechanics than Hamiltonian, but considering position and its time derivative (velocity, or momentum) being independent when solving the Euler Lagrangian equation, is the same than in Hamiltonian mechanics. And actually, I have the same question as you do. Why do we do that while intuitively, know x and v are dependent. From my research on Internet, it appears to be linked to the approach taken. This dependence is actually what we are trying to find (a differential equation that can then easily provide a function of position with time). So we start like if there was no dependence and see what happens... When solving the EL equation at a given time, we do not have a known path for the least action integral: At any position can be associated any momentum and vice versa, which lists all the possible action paths. That is why we can initially consider these as independent, in order in the end to find their dependence! (which is actually solving the problem by finding the differential equation on position.) I am not sure if I am clear (or even if my understanding is correct for that matter), but here are the links I found that could be of interest if you want to dig: www.quora.com/Why-is-velocity-considered-to-be-independent-from-position-in-the-Lagrangian-formulation-of-Classical-Mechanics www.physicsforums.com/threads/why-are-position-and-velocity-independent-variables-in-a-phase-space.883013/ physics.stackexchange.com/questions/168551/independence-of-position-and-velocity-in-lagrangian-from-the-point-of-view-of-ph#:~:text=Since%20Lagrangian%20is%20calculated%20at,velocity%20and%20position%20are%20independent. You actually threw me out of my comfort zone with your question. Thanks! That’s the real fun of it, because it makes me progress too (a teacher is just an eternal student!)
Hello sir Sir while explaining surface tension you mention that the surface tension acts along a line (boundary) , when the surface is flat. But what will we happen in the case of a sphere (curve surface), and if such things happen then , doesn't it will be on a single point of contact with surface of water??? Also sir as we know, earth is moving around the sun in an accelerated motion , so at every instant when earth changes its direction, why don't we feel inertia of direction, as the earth is moving with way high linear velocity???
Hi Kim, Surface tension : In the case of a sphere, that would probably require a little calculus, where the variation variable could be the angle of the interface with the horizontal (or the distance from the center of a disc). In that case : the extension between water molecules will vary with the distance from the center to the extremities. You could imagine co-circular lines of iso-tension. If you average-sum all these surface tensions, due to each circle (considering mass variation too), you would get something inferior to a flat disc. That’s why a sphere will sink more. (Sharper the entrance to the water, more easily the object can sink.) Rotational inertia : We actually do, but the effect is very small comapred to gravity. But if you consider the effect due Earth rotation instead, there the effect is significant : The apparent gravity at the equator is 9.78 m^2, and at the poles 9 .83 m/s^2 . Another effect of rotational inertia is the coriolis « force » (note that it’s not a force , but it appears so due to inertia, like the centrifugal force)
Hi R, Thank you for your kind comment. Inductors: well, I wanted to do so but I have too much on my plate these days. These videos requires a lot of time to produce, a commodity I do not have in heaps! Yet, it's still on my list (along other topics) for when my busy agenda frees me again!
Hello sir It's a short one, We have always been told that the formula to calculate the angular displacement/theta is given as (l/r) but as a side note is given "only for small angles". Why it is so sir?
I guess because in the calculations that derive the formula, there must ne a point where you need to use the small angle approximation (where one assumes that sin (angle) = angle)). By using this, the formula obtained will only be reasonably accurate for small angles (usually less than around 10-15 degrees).
Sir I have one more confusion from sound. We are taught that the sound wave are longitudinal waves. And we convert them to the graph of pressure or density variation versus distance. the amplitude is defined as the maximum displacement of the particles, and for the sound waves maximum displacement of particles is horizontally ( left and right) . But still we denote the amplitude of sound as the maximum variation in pressure or density, even though the the si unit of amplitude is meter. Please resolve this confusion sir.
Hi Kim, the Y axis of sine graph representing a longitudinal wave is not pressure or density, it is displacement versus the equilibrium point (that is Y = X - Xeq ). I have seen text books making the mistake you describe, or maybe not explaining clearly how they draw such density graph... If you consider the positive direction for displacement (i.e. the positive direction of the Y axis) as being displaced to the right, the maximum density occurs on the x axis where the sine curve crosses the axis and has a negative gradient (at this point, particles to the left have a max displacement to the right, and particles to the right have a maximum displacement to the left, which leads to a maximal compression). The same way, the rarefaction points are when the sine curve crosses the axis with a positive gradient. Think about it...
Hello!!! I love your point of view on explaining these physical terms, found it very helpful!! thx!! Having one interesting thought here, as you mentioned when we put a dielectric material into the capacitor, as which having a much higher permittivity (than air), it will requires more charge to be build to balance out the effect of the induced electric field. Now, as we increase the permittivity of the dielectric, more charges can be stored, to the point the permittivity is infinite (like a metal), what would happen, assuming we can have some sort of barrier to prevent the charge to go through the metal. are we creating a plasma here :)
Hi, Interesting, but I see a problem with your reflection: you assume a barrier that you place to prevent charges from passing through the material of infinite permittivity (a metal). What you are doing here is creating two capacitors in series (the di-eletric used for both capacitors being the charge-blocking material)... That changes fundamentally the configuration you are trying to explore...
Sir I have another one, actually two, First, sir in our homes there are plane mirror, and its very common. But sir when I touch the mirror surface still some gap is present between the virtual image and my image. I thought it was due to the width of the mirror but what is the actual reason sir? Second sir ,the ropes that are present in our homes where we put cloths to dry , when left undisturbed why they bulges outward more from center as compare to other portions?
Hi (what's your first name?) 1/ the reflective part of a mirror is the thin metallic layer behind the glass. When you place a finger on the mirror, the gap you see is twice the thickness of that glass. 2/ What is instead of a rope you placed a metallic bar? It wouldn't bulge. The bulging of the rope is due to the material properties of that rope. more specifically how the bonds between molecules respond to external forces.
Sir, would you please explain the following? Does free space and air that we are breathing mean the same thing ? How the permittivity changes between this two ? Mathematically,i proved e(epsilon) for air is equal to e(epsilon_naught). Iam really confused between this two. Hope i get cleared sir P.s iam currently working on maxwell equation derivation sir
Hi sgiri. Compared to condensed matter (= solid or liquid material), air contains a very low concentration of molecules. Therefore, the effect of these molecules on the electric field will be minimal, barely significant when you compare with the effect of the huge amount of molecules in condensed matter. Consequence of that: the ratio of the permittivity of air with that of vacuum is very close to one: 1.0006 to be exact. Does this help?
Sir does circular instantaneous speed and linear instantaneous speed is 100 percent same or there is any difference between very small displacements on circular track and linear track?
Hello Rahul. angular speeds (what you call circular I suppose) and linear speeds are not the same thing. Linear speed (LS) is distance per unit time, angular speed (AS) is angle covered per unit time. The relation between them is the radius (LS = AS x R). This relation applies for both instantaneous or average speeds.
@@rahulkajala25 Imagine you would put a mass at the end of a rope, and spin it (no gravity, no air resistance: you are in space). The speed of the ball would be omega x R right? Suddenly the rope is cut ... What would be the speed and direction of the motion of the mass after that event, still the same (there is no acceleration anymore, so V = Omega x R). and the motion would be linear. In other words, the speed of the ball perpendicular to the radius (what you call instantaneous speed on circular track) and linear speed are the same concept.
Hello sir i have a little question. Why does the size of the image(everything) gets smaller and smaller than the object , when object is placed between two parallel mirrors?
Sir I have two more questions 1) Sir suppose we want to find the work done and given is that force (f) is a function of displacement (s) as f(s)=f=s². So integration should be done from 0 to s , and I did and got s³/3.But sir if want to find the final velocity (v) than can we equate the W to 0.5mv². I was confused because it's for uniform form force and here it is variable. And if not then how can it be found sir? Time 2) sir suppose we have a Blok of mass m in the air(but no drag) at height h, so gravitational force acting on it is mg. Now we apply a force of equal magnitude but in opposite direction to balance the forces. Show the block will either be at rest or it will moving with a constant velocity. And here I assumed it to be going with uniform velocity in downward direction and covered the height h. Now both the forces are still acting so there must be some work done by them: for the gravity mgh and for the external force -mgh. So there is net Work done 0 and so it doesn't accelerate. But while approaching downward is potential energy decreases, and my question is where that potential energy lose? Please explain sir
Hi Kim, 1/ Because Energy is a conserved quantity. The way the object got it (with a constant force or not) does not matter… The work done by the force resulted in some energy provided to the object. If that energy goes fully to the object as KE, then that KE will be equal to the work done (s^3/3). You can write W = s^3/3 = 0.5mv(final)^2. 2/ We will suppose on a planet with no atmosphere (no air). How would you apply that force? You would need a flying vehicle with a rope holding the object so that tension in the rope would balance the force of gravity. How would you keep the vehicle from accelerating downwards… (make it fall at a constant speed), You would need to use energy (propulsion upwards just enough to counter grav. acceleration). … I let you finish the reasoning 😉
Sir I want to know from you that why magnetic lines of force form closed loops and what is the logic behind the fact that outside magnet they originate from north pole and terminate at south pole whereas inside the magnet they start from south and end at north pole .
Hello Shadma. In classical physics, a field is continuous. The consequence is that the field lines must be continuous, this is why these must be closed loops. And this is also why when a field line enters a south pole it continues to the North.
@Physics Made Easy hello sir, as you have recommended to search for state functions and I did but I find something very confusing. In almost every video it was said that heat and work done are the two most common examples which are not state variables or state function. It means that while doing work, the work depends on the path of the object that it took and it seems obvious because the formula itself is force into displacement. But sir it was also taught work done by a gravitational field on an object does not depend on its path. So it is also state function because it fits in the definition of the state function. Is it so sir? I have one more confusion related to this, whenever there is a situation in which it is given that an object of mass m is lifted by someone, so we take that the force applied to lift the object is MG , this means that the object is moving upward with a constant velocity but what if the force applied is not mg? Why we always take MG in this type of scenario sir even though it is not always ?
Hi Kim, Work and heat are not state functions because these are energy transfers not energy states… You change the state of an object by heating it or working on it. For example consider hunger as a state function. Weather you eat bananas or rice your hunger will become small. And whether you eat your portion fast or slowly, your hunger state will be the same at the end of your feast. Your second question. When you apply a force equal to mg for a height from 0 to h, it means you provide work equal to mgh. Because the net force is balanced, there is no net acceleration, so no increase in speed, so no increase in KE. All the work you did went into PE, which is therefore mgh. If your force is > than mg, the object will accelerate so the KE will increase. Your work Fapplied*h will contribute both to the PE and the KE. I hope this helps Enjpy the year end celebrations!
I request you to make many more awesome conceptual videos like this regarding electromagnetism. We cannot grab the concepts by merely looking at the books though we are graduate students. 🙏🙏
I would like to, but too many things on my plate right are interfering with my TH-cam activities ... You are 100% correct regarding how to learn things: Reading books is not enough, you need to reflect on the notions you encounter and compare your understanding with others (for example reknown TH-cam videos). Then, don't forget to train that knowledge with exercises and problems ;-)
Hello sir! I am in one more confusion, Sir the formula of kinetic energy, 0.5(mv²), works when the force acting on a body is constant , as while deriving this equation when used equations of motion. And if the force is variable we can take the help of calculus. But sir when ever we examine a problem in which mass, say m, and its velocity , say v, is given we blindly apply the above formula to calculate its kinetic energy. I suppose, that the value of K.E we just get is the work we have done on a body with mass m, initially at rest, and to bring it to velocity v, with a constant force. This is my main doubt, that when we have this scenario we don't know whether the body has acquired that velocity with a constant force , though we do this. Isn't it very uncanny sir?
Hi Kim, Because Energy is a state function: the energy of an object does not depend on how it got it, it only depends on the state of the object at the present time. Google up ‘State Function’ to know more 😊 !
@@PhysicsMadeEasy hello sir, as you have recommended to search for state functions and I did but I find something very confusing. In almost every video it was said that heat and work done are the two most common examples which are not state variables or state function. It means that while doing work, the work depends on the path of the object that it took and it seems obvious because the formula itself is force into displacement. But sir it was also taught work done by a gravitational field on an object does not depend on its path. So it is also state function because it fits in the definition of the state function. Is it so sir? I have one more confusion related to this, whenever there is a situation in which it is given that an object of mass m is lifted by someone, so we take that the force applied to lift the object is MG , this means that the object is moving upward with a constant velocity but what if the force applied is not mg? Why we always take MG in this type of scenario sir even though it is not always ?
Sir I have one more from your previous video about why the gravitational potential energy is negative . I got confused when you said that you were choosing the scale. You had chosen the scale in such way that the force applied by us is positive, but what if we reverse the scale, in that case force applied by us is negative and on further calculation the gravitational potential energy is coming positive. Where I am wrong sir?
Sir I have question about tension, sir we always consider a string to be massless because that implies that the tension force is acting uniformly throughout the string but sir when it comes to a string that have mass , it is said that the tension force will not be uniform. Moreover the tension force will be maximum at the end where the force is applied and it will be least at the free end. But sir no one give me the reason for this scenario why it happens ?please explain this, because sir considering a string to be massless is equivalent to considering gravitational force as repulsive because if there is a matter it should have some mass? Won't it affect the result?
Hey (what is your first name?), Strings are considered massless because it simplifies grandly calculations: You can consider the string like a single system when you draw a Free body diagram. If it is not, you need to consider the strings like a set of tiny systems of length dx in order to describe accurately the system. Usually the mass of the string is small compared to the mass of the thing that hangs from it, so it is reasonable to neglect it. Now to your question, I’ve been thinking about it. I do not have a straight forward answer, but if did dive into it, that is the model I would use to start working on it: Consider a string made of one single massive particle and attach it to two walls with strictly massless rigid bonds. Do a FBD on it and derive the forces (direction and magnitude) Now, consider three particles instead of one (the bonds between the particles remain massless and rigid). Do a FBD on all of them and derive the forces. Repeat with 5, 7 … N where N is an odd number From this work, you should be able to generalize tension as a function of position.
Nice video and presentation. Dielectric is something that pass (permits) electric (charge) into a space occupied by it. We know that vacuum-space holds electrostatic, so itself is also a dielectric, the size of a universe. As it permits electric into the vacuum-space, it also responsible for light propagation within the vacuum-space. Further? Vacuum-space is a dielectric with no physical but electrical properties, permittivity, known as e0 or Aether. So light from distance stars can reach us because of e0 or Aether.
Hi there philoso, First, a dielectric lets the effect of a charge (the electric field it generates) pass through it, not the charge itself. And yes, you can say that because vacuum has a dielectric property (eps 0), light, which is basically the propagation of an oscillating electric field, can pass through it. And yes again, that is why we can see the stars at night.
Thank you so much for your kind words! I am glad you enjoy what I do. I will keep creating content, that's for sure, it's a hobby, but as all hobbies it need to be at a suitable pace ;-).
Bonjour (hi) sir.... I have one doubt in dipole moment.... Dipole moment will happen when electric field passed through it????? Can you pls reply sir...
Semiconductors is just a type of material that conducts electricity in certain conditions and not in others. to explain how it works, there are quite some notions to introduce like band diagrams and doping, it's more for a video than a comment, so I keep your suggestion in mind :-)
Sir I have a question is that,in the sun core nuclear fusion occured and it emits highly energetic radiation called Gama rays. So it emits gamma rays but we get UV rays how's that possible.sir explain us clearly
Hi Shivam, indeed gamma rays are produced in large quantities in the Sun's core... but in order for these to reach out, they need to leave the core and go through all the other non fusionning layers of the sun. By doing so, they collide with a lot of matter which results in the ray losing its energy and the production of lower energy photons. hundreds of thousand of years later, when it finally reaches the surface, the gamma ray is a not gamma ray anymore because it lost a lot of energy in that process. As for the UV light, it's another phenomena: Black body radiation. Close UV (the one you are referring too I suppose), is the end tail of the spectra (around 200nm). Much hotter stars than the sun emit a much higher density of UV light. I wouldn't enjoy living on a planet around such a star!
Hello sir I am Kim, i have more and it is about surface tension. Sir the definition of surface tension is given as force acting on a unit length perpendicular to it. But sir consider a blade, though the blade is denser than the water , if we gently put it on the surface it will float. Sir here water particles are attracting the blade particles through out the surface, but surface tension is N/m ( N/m²). I feel it very awkward because , in questions also we are said to take the boundary (perimeter) of materials, not the area of contact with water. Sir please clear this? One more ( Diwali 🎁), sir in calculating friction force we just use normal reaction and coefficient of friction. Sir but in daily life (from my frame of reference) it seems to be also dependent on the velocity. For example, at garage , when the grinding machine is used , that spin at high velocity, the sparks come out , but if it had spun slowly nothing happens. Why sir? Also sir it is said that the static friction is greater than kinetic friction because while moving the irregularities don't interlock perfectly as compared to when they are in static state. It means that at much higher velocity irregularities won't be able to interlock perfectly, as they would directly jump on to the next portion. It means that at extremely high velocity is the friction should decreased to a large extend but it don't happens? Why sir?? Also sir, the composition of atmosphere tell such that in what percentage certain amount of gas is; for example nitrogen 78%. But sir my question is that which quantity does this percentage indicate, first time thought it to be volume but sir as we know air is a homogeneous mixture, so volume of each gas should be the same. So my question is which quantity does it represent whether it is moles or in the terms of mass? Please sir...
Hi Kim, 1/ I encourage you to revisit your understanding of surface tension. Surface tension is a property of the interface related to the amount of intramolecular forces that occur between water molecules along a line S = F/l. These forces are larger at the interface than in the bulk. Once you place an object on the surface, the distance between molecules of water will extend, and like a spring generate an extra return force. The direction of the force will also change gaining a vertical component. That vertical component compensates for the weight of the object. The object appears to be floating. Visualise it: Naturally, the extension of the surfacic bonds between water molecules only occur at the perimeter (assuming the surface of the object is flat). 2/ You are confusing energy and force… P = fv. For the same amount of friction (f), with a larger speed v, you will dissipate energy at a larger rate (P)… hence the heating and the sparks. 3/ Usually, the composition of the atmosphere is provided in ppmv (parts per million in volume). It’s more intuitive because in normal conditions, the volume of one mole is the same whatever the gaz. If you know the molar masses, converting to the the mass fractions is easy.
Hi Kim, your question is a little out of my field of expertise. For me it makes sense and would be in relation with the angles formed between the normal between the intersecting plane and the surface areas of the cone at all points. But I do not know how to prove this mathematically. You should ask your Math teacher!
Hello sir , I have some confusions. 1.) Sir I have observed that in almost all the water taps I have seen , there is a strange pattern. First when the tap is opened partially or very little , a laminar flow of water is observed but then turbulent flow is observed when th tap is opened completely. But the odd thing is that pattern I turbulent flow is observed repeatedly, meaning the next when we have done the same the same pattern of turbulent flow appears like one end it is thinner or any thing else. Is that pattern is predefined? 2.) Sir whenever I see bubbles or foam I any liquid, whether water or milk, the bubbles gradually move towards the boundaries of the glass or containers . Why it is so? 3.) Also sir when a bubble is formed on the surface of transparent liquid, then the light intensity at bottom of that bubble increase. Why this happens sir ? Is it acting like a lense?
Hi Kim, Question 1: I do not understand your question. Please reformulate. Question 2: To minimise surfacic energy. Question 3: Yes, there will be refraction occurring when light passes through the bubbles surfacic layer. Under the right conditions, it could act like a lens. It can also act like a thin film with constructive or destructive interference depending on the wavelength, incident angle and thickness of the bubble surface. This is why soap bubbles can look all iridiscent, and when they thin out, they lose this iridescence and become all transparent.
Dear sir, Please have a read through sir. You are amazing at the explanation of concepts through logical reasoning. Please 🥺🥺 have a look at this sir. Would you please take separate lecture on the following topics via online media ? I will separately pay for you Iam barely in need of topics in optics mainly michaelson interferometer and how circular, localised and unlocalised fringes are exactly they are formed ? How it naturally leads to the formation of the alternate bright and dark fringes ? Who on earth ordered light to do so ?(when I search for answers,it gives that it is due to the fact of phase and path differences between the waves), but why this is the case ? When I looked up articles that discusses interferometer mainly michaelson interferometer, I found another interesting topic called michaelson Morley experiment and it is one of the famous experiments which disproves the presence of ether in the atmosphere. Is this is the same principle applied with interferometer ? What is the connection between formation of fringes and the presence of ether in atmosphere. Please consider and take classes for me. I am only dependent on you sir. If you take classes for me😊, i will so happy sir
Hi Sgiri, thanks for your message. If you are searching for a tuition from me (high school physics, IB, AL and AP1), it might still be possible. Check my tutoring website www.physics-tutor.nl/ and write to me through the website after looking at the tuition conditions. About your question. Try to look at the theory related to waves first before looking directly into an application. The fringes are called fringes of interference. Take a sine curve, copy it, then shift the copy by a half wavelength. This creates phase shift of pi between the two waves. Add the two together, and the result will be a flat line. If the sine curves were light, you would get darkness as a result. An interferometer takes a ray of light, generates a reflection, and adds the reflection to the original beam. The difference of distance travelled between the original and reflected ray (called path difference) will have an impact on the resulting wave. This is how one can detect extremely small differences of distances (like the LIGO interferometer measuring the tiny distortions of space time due to a fusion of black holes billions of light years away). But first forget about the interforemeter and familiarise yourself to the phenomena of interference with a good textbook. A good start is to look at how 2 slit diffraction works. Your questions shows that you first need to clarify this. Good luck !
@@PhysicsMadeEasy sir,once I got clarified with this I will tell you. Thanks sir. I need separate tutorial on that Michealson interferometer. I will make sure to familiarise in the ocean of interference
Happy New Year sir , I am in one more trouble. Sir the law of reflection states that the angle of incidence is equals to angle of reflection. This is said to be applicable with all types of mirror whether it is plane mirror concave mirror or convex mirror. And also when we draw a radius (of any circle), it is perpendicular to the tangent to that point so it acts a lot like a normal for a Mirrors. But my confusion is with one of the rules of concave mirror which is stated as if the incident ray is parallel to the principal Axis then the reflected ray will pass through the focus of the circle ,which is Halfway between the pole and the centre(of a concave mirror). But when I have drawn a concave mirror with Centre C and Pole P and focus F and taken and line l parallel to CP(radius) and let the point where it touches the mirror be O. So when we connect C and O, CO should be the normal which means that the angle between CO and the parallel line(incidence ray) should be equal to the angle between CO and the reflected ray, so when I have done so I found many times that it is not passing from Focus .The line which passes through the focus does not have the same and angle as the incidence angle. Where am I going wrong sir I have tried it many times and all the times I am getting the same result. Please clear this confusion sir ???...
Oh, Kim, you are always in trouble 😉 What you are experiencing is called spherical aberration. The rule that rays parallel to the principal axis will focus on a single point is true for parabolic mirrors, but not for spherical ones (like a concave mirror). It is approximated true for spherical mirrors when the radius is large compared to the size of the mirror itself, i.e. for a small aperture. Check this link : it has a great picture that explains it all : phys.libretexts.org/Bookshelves/University_Physics/Book%3A_University_Physics_(OpenStax)/University_Physics_III_-_Optics_and_Modern_Physics_(OpenStax)/02%3A_Geometric_Optics_and_Image_Formation/2.03%3A_Spherical_Mirrors
Thanks for everything you do and teach me dude like your videos are the best way to find a source thanks for everything keep it up and keep posting these kind of videos thanks bye :D🙂
Thank you Alex for your kind comment. I am glad you can use my videos as a starting point to dig a little deeper. It's the whole idea behind this channel: Help students grow their own wings! :-)
Hello Arnav, Thank you for the kind wish... Millions of subscriber, maybe , I should be careful for what I wish for haha: How could I keep on answering all comments / questions haha! Direct currents: electric charges move always in the same direction. Alternative current: they oscillate around a central point (they go back and forth in a cable). They do so because the voltage oscillates too (they are continuously pushed one way, then the other)
Hi Fi, Here's a starting point for that question: www.sciencedirect.com/science/article/pii/S2211379717317230#:~:text=Highlights&text=Proper%20use%20of%20magnetic%20field,change%20the%20properties%20of%20water.&text=The%20evaporation%20amount%20of%20water%20increase%2038.98%25%20after%20magnetization.&text=The%20specific%20heat%20and%20boiling%20point%20of%20water%20decrease%20after%20magnetization.
I enjoy physics but sometimes I start questioning myself" Am I studying it the right way?" " Can I explain physics in my own words or even my own mother tongue?". These questions sometimes even disturb my sleep. Sir please once say that "Physics is all about understanding and application and not rote memorisation"
Absolutely Sandeep. Actually, you should look at the pinned video presenting the channel which confirms your thoughts on the subject. If you can explain rigorously a concept with your own words, it is a proof you actually understand deeply the concept, and thus know how it fits in the big scheme, as well as reflect on applications. But, do not let this disturb your sleep... ;-)
@@PhysicsMadeEasy thank you so much sir and I now promise I would think more deeply about physics concepts and not hesitate to explain it in layman. PHYSICS IS AN ADVENTURE
I would be interested in how this concept applies to human biology. Are we dielectric? If so, do radio frequency fields and EMFs change our bodies? Anyways, thank you very much for the video and the others. They are very well done and I will keep plumbing through them for insight.
Hi Mike, Yes, because we are mainly made of water but the effect is minuscule, properly insignificant, compared to the random motion due for example to temperature. For a significant effect, the intensity of EM waves would need to be huge. btw, the light from the sun is also an electromagnetic wave... And thank you for your kind words :-).
If my work can help students in Kazakhstan, Sure! Please refer to this channel in the video, and in the description. Let me know how this goes. I love to see how the human fascination for how our universe works, has no cultural nor physical borders :-)!
Hi Mamata. Thank you for your kind comment. I am happy my videos help you clarify things :-) Good luck with your studies (imho, the real physics fun starts in Grade 11 !)
sir what question do science or physics ask to nature like do physics ask why things happen or how things happen or both or something else ? what is physics..................
Ahh a philosophical question :-). imho, Physics attempts to explain the how, not the original why... Many (non scientific) people oppose science and religion, but in truth, when you study and understand physics in depth and realise the amazing beauty of how things work, it can fill you with awe. Result: more than half of the scientific community beleives in some form of higher power or deity. (PS: And I am saying this as a non beleiver! Meaning I do understand why so many believe,and respect their belief)
can you explain why asking " why " does not make sense or give your detailed views on this in any ways you comfortable with video or reply or shorts or any thing . i would love to know 😌
@@x5dot No we can't... For example, we were able to retrace back to the big bang, but we do not know really what caused it... There are lot of ideas and theories about that, and one day, we might find out. But we'll again wonder from where what caused the big bang came from in the first place. And this can go on forever, in an infinte cycle, where a new discovery ends up with a new question...
I watched your video why gravitational potential energy is negative. Can it be < when we displace a body from the surface of the earth , we do some work which is stored in its potential energy. Since the force of attraction is towards the centre of the earth and the displacement is outwards the centre of earth so the work done will be negative as the gravitational force . so will will be negative and so the Potential energy will also be ZERO.
Hi The work done is positive: in W = F x D, F is the force applied on the object to move that object, not the force of gravity (it is opposite to gravity). F and D are both in the same direction. The PE becomes then less negative... (It is zero when both objects are infinitely apart).
Thank you very much...the dipole has always been a scary topic for me. Also sir, is it possible for you to activate Super Thanks? so that people would be able to support the channel?
You see Tirthankar, dipoles are not that scary after all ;-) Thank you very much for your suggestion, I didn't even this feature existed! I just activated it.
Felicitations. Vous fournissez un superbe travail. Grace a vous il me sont deja clairs certaines notions fondamentales. Si vous pouviez Donner une explication comment les Ovnis peuvent Faire des virages a 90 degres sans ecrabouiller l^еquipage en manipulant lespace-temps....
Haha, je crois que si j'avais la réponse à cette question, j'aurai déjà construit et breveté le moteur correspondant ! Et serais probablement richissime !
When we are child no teachers teach like this. This Generation is lucky.
In high school, I struggled like crazy because all my science / maths teachers were either incompetent, or just in their own bubble. I was lucky that in Uni, to enjoy the teachings of great professors that really loved their job and cared about their students. These have been my role models, and now., that I am much older and wiser, I give back... especially at the level where there is the biggest lack of good teachers.
“First, a dielectric lets the effect of a charge (the electric field it generates) pass through it, not the charge itself.”
What do you think of an alternative view?
a dielectric lets an electromotive force to push / build charge in it and not through it.
I had to review math by myself at 40, and now I understand derivatives and integrals. Teachers were just bad in the late 90s/early 2000... I didn't understand a thing back then!@@PhysicsMadeEasy
Thank Jesus.. God bless you!
Even now no one teach like this
Your channel is so underated but it's a gem💎
Thank you Kuldeep! It encourages me a lot!
I've never really understood capacitors until your past two videos, now it makes perfect sense. Thank-you!
Thank you Spencer. I am happy I have lifted the mist for you about these super important electric components!
This is another great video. The analogy with mechanical energy stored in a spring at the end really does add a tangible image that pulls it all together. The meaning of equations, even simple ones, can be quite elusive.
Yes, that is why I made this analogy... Many find these equations quite abstract, the analogy allows to make it more concrete. What you can try is look at other equations, and try to find a tangible picture for these two. Feynman does this a lot, that's why he is a great teacher. For example, I really enjoyed his analogy between RLC circuits and a damped mechanical oscillator (his lessons are downloadable for free online as text).
So, im translating everything to field theory terms in my head, but man you helped so many things click for me. Its very difficult to find such a full description on this subject
Thank you Noah, I am super glad I could help make things click for you :-)
Thank you so much for this video - very clear, particularly appreciate correct closed captioning added by you! automatic is so unreliable. hugely appreciated.
Thank you so much Cerys! Your comment is very much appreciated, because to be honest, it is quite a lengthy process to write these directly in the editing software. But it is a step I always do before the final rendering: I know that if I were a viewer of the channel, I would appreciate this: The subtitles in TH-cam are not always accurate, hide too much space of the screen and are really not aesthetic!
I wish I had found your channel earlier, it would have made my college life easier. All thanks and support to you from Egypt to where you are, man💙
Hello Marwa, I am super happy to read this. This is exactly why I make these videos: to simplify student's life, so they get a conceptual understanding and then dig deeper in their teacher's or professor's lecture with improved confidence!
I kept thinking "dielectric" must have two of something, like "dipole". Until this video, I didn't know it meant going through something, "dia" as in "diagram". Thank you for pointing that out. Good video.
Cheers William. same here, when I was a student I associated the di to 2, like in dipole... I suppose many students do the same faulty association... I thought it was important to do this little etymology section to put things straight! My assumption was therefore right: I am glad I clarified this for you.
I watched your video for the first time and within 2 mins of watching I subscribed to your channel. Thankyou so much for clearing the concepts so well.
Hello Arya, thank you very much for your kind words. I am glad my work clarified these notions for you!
It was an excellent explanation, I learned so much from it. It is wonderful to learn from teachers who can explain things this clearly and tangibly, which also shows their profound grasp on the subject and it really translates to students. Merci beaucoup Professeur !
Je t'en prie Melisa :-)
Thank you for your kind words, I am glad my video helped you!
@@PhysicsMadeEasySir Your explanation is really very effective. Please try to make videos on other physical quantities too.. Mind me If you think that it takes a lot of time to edit them or whatever, your makingtheconceptsclear quality will be as effective on a simple white board too..
This stuff is here for free. Its a great opportunity for anyone to learn pretty much anything.
Maybe not anything, but Physics, oh yeah! ;-)
I think it's pretty awesome that my TH-cam Channel analytics shows this video as being one of the top videos suggesting my rap music afterwards.
Physics and Music are deeply entertwined!
I am actually a musician myself, and earn a fraction of my living from he royalties of my music work.
When I used to teach face to face, I would invite my physics students to the studio and show them how various sounds could be made by interference of various sinewaves (in other words, sound design using a synth).
It's beyond amazing, the vedio actually instills the thirst in me to acquire more about dielectrics. Love from Pakistan.
Wow, thank you for your kind words Kabeer.
If I can inspire love for physics in people, that really shows I am doing it right!
@@PhysicsMadeEasy of course, to be honest I am waiting for your next vedio, it would be great if it's about Quantum Mechanics.
Thank you for your effort sir, I was able to understand more clearly about dielectrics
You are welcome. I am glad my work helps!
"Electromagnetic Fields & Waves" (3rd ed.) by Lorrain & Corson covers dielectrics in Chs. 9 & 10. I used the 2nd edition as an Undergrad back in the day.
This is a very informative video about dielectric. I learn a lot from it. Thank you so much for teaching us this.
I am glad you enjoyed this video: I remember putting quite some work on this one, so I am happy it was helpful to you :-)
Man amazing video, this channel needs more attention
Thank you Parahumour
Sir, I am a lover of physics and your videos motivates me... Love you from India... ❤️❤️❤️
Thank you Md Nurain! I am glad my videos reinforce your love for physics!
Hats off to you sir, very good explanation now I'm able to understand dielectrics correctly. Thank u so much
Love u from India 🇮🇳
Hey, I am glad I was of help! Thank you for letting me know!
Interesting way .. thanks alaot 🎉
Hello Sir! This is the best physics channel that I have come across so far❤...and this channel is perfect for physics lovers like us😊😊...This was the kind of channel that I was looking for a very long time!!! ❤❤.. Physics is a fundamental part of our life.. It is something that we can observe, analyse, and experiment to study details of nature...we should enjoy learning like the way you're teaching....Excellent explanation!!!!... Looking forward to more videos on particle physics, light energy, high energy physics, and many more❤❤❤
Hi Swarali. Thank you so much for your very kind words, and pointing out our common passion!
Thank you also for your suggestions of new videos. You seem to enjoy particle physics: maybe you have seen that I made some time ago a playlist on the subject.
Feel free to visit it (th-cam.com/video/gy-durcAhJ4/w-d-xo.html)
Bonjour (hi) sir..
I have doubt in dipole moment.....
That dipole moment will happen when electric field passed through it ????? Is it right?????
Could you pls reply...sir...
Dipole moments do not necessarily need an external field to exist. For example, a water molecule is polar by structure. In a glass of water, the molecules are oriented randomly so there is no net dipole moment for the glass of water. However, applying an electric field will orient all the dipole moments of the water molecules generatiing a net electric dipole for the glass of water
But applying a field , one can also create electric dipole moments in a medium composed of positive and negative charges that are uniformly dispersed. In that case, you can get also a net electric dipole moment. I recommend you check my video on magnetic dipole moments, it could help: th-cam.com/video/lG1TP5-rKfM/w-d-xo.htmlsi=7wEytIHJeieiQggR
@@PhysicsMadeEasy sir thank you so much sir you are the first physicist for me who gave me reply.......
This is exactly what I need. Im building something and this channel will help me. Thank you
I am glad that my video helped you with your project. Thanks for letting me know!
THANK YOU VERY MUCH!!!🙏
I understand a lot of ideas from your videos that I can't understand in school, College and University.
You are warmly welcome. That's why i am here: to debunk the basics, so that when you go back to your class notes, you see the light :-)! Thank you for letting me know, it really encourages me.
@@PhysicsMadeEasy
ofcourse I see the light! But I am A communication engineer now. N.B I didn't wrote this comment for only this video, but also for all of your videos. I have watched most of your videos and I have answered my all doubts. Again I want to say you Keep it up...and Make the illusion to be clear. You are the light to see all technology and physics. THAK YOU!!!👍👍❤
Wow 😲, amazing explanation
Thanks sir, could you recommend any books that help in visualising how electricity works?
Hi Abdulraheem, unfortunately, not really. Still, the lessons that I found the most inspiring , and that I use when I have a doubt are the lectures of Richard Feynman. These are free on the web to download. But these are also very dense (every word counts), and you need a at least an undergraduate math background to fully understand the content. I hope this helps!
You're the goat man tysm for this, cleared everything and made it super simple, so grateful that i found this channel 👑👑
Hi Lil, I'm glad my video cleared the path to new understandings for you !! Welcome, and explore the channel, there is a ton of stuff now...
Thank you Sir. I have learned many things so easily. Hope that this channel will make million subscribers ❤️
Thank you Ferdows... 1 million subscribers ??? Maybe in 2070 haha!
at 6:55 assuming epsilon approaches to infinity, E' goes to E, Er(=D displacement field) disappears, but when epsilon approaches to infinity and still finite, Er(=D) still goes to zero, while E'(=P due to polarization) approaches to infinity, i found this contradiction in EM theory.
how high can an epsilon go without being broken away to be free?
even if they are free, but the bulk of the left free MUST be equal to the bulk of the right "HOLES" that which should be considered the macroscopic polarization..... fine fine E can be discontinuous but must be conservative without changing B field present.
I am not fully sure I understand your comment (I feel there is an interrogation behind it that I do not see clearly).
What I know is that permittivity cannot be infinite in the real world... It is a property that depends on the charge structure of a material. In any material, there will always be a limit to how much it can get polarised. Without limit, it would not be a dielectric anymore, because there would not be any polarisation but a current flow....
If you wish to consider epsilon as infinite: that means there is a current instead of a polarisation... It's not a dielectric anymore but a conductor or a superconductor.
If you wish to say it tends to infinity (without reaching it), you are inventing a theoretical material... Maybe you can find an answer to your question by checking out more in detail ferroelectric materials, these tend to have very high permittivities, and then extrapolate from there..
My answer was probably not very helpful here, but maybe it gave you a lead to investigate further.
@@PhysicsMadeEasy i think my confusion came from here, the higher epsilon the better the capacity is in formula, so why not using salt water ( epsilon=80~88 instead of paper or plastic) but salt water conducts electricity. and when epsilon goes to infinity, the material goes to be like a conductor. the higher the epsilon meaning E (external E) is NOT passing through well, but P(polarization or induced E) will rise and store more energy into the material, so dielectric permittivity(electric field passing through) should take the max value for air and min value for matal. but they are apposite, min value for air , max for metal. why or how?
@@abcdef2069 Let’s go back to the definition of permittivity : It is the ability of a material to resist the formation of an electric field inside it. Metals are conductors, so as soon as you try to apply an electric field on it, the electrons in the metal are going to move along the field lines until they find equilibrium: When they finally do, there is now in the metal an electric field that cancels the applied field. So there is no resultant field in the metal.
That’s why the permittivity is theoretically infinite for a metal. Finding an infinity, is very often a sign that there is something wrong with the reasoning: And what is wrong here is to assume that a metal is a dielectric … It’s a little like if you were measuring the hardness of a liquid… A liquid is not a solid.
I hope this idea helps.
Amazing!!! Your Videos enhances way of thinking.. Keep it up Sir! Our prof. also explained (Why capacitance increases due to dielectric) by breakdown voltage concept also..
Thank you Parmanand. Breakdown Voltage is more related to when the voltage, thus the field is so large that it can modify the electronic structure of the material. Basically the electric force becomes large enough to strip atoms / molecules of some of their electrons. This usually results in damaging irreversibly the capacitor.
@@PhysicsMadeEasy okay... Got it..
Beautiful articulation of the of the induced dipole moment phenomenon.
Sir by Gauss theorem , electric field between two opposite charges is the sum of electric field of both charges and resultant has more magnitude than electric field exerted by them individually . Then how can resultant electric potential gets decreased when the relation |E| = |dv/dr| shows that they are directly proportional to each other . Hope you would reply.
Yours sincerely
Talmeez Abbas
Hello Talmeez,
you wrote: "Sir by Gauss theorem , electric field between two opposite charges is the sum of electric field of both charges and resultant has more magnitude than electric field exerted by them individually ."
Be careful. you should have said: "the vector sum". If you consider a point between the two positive charges, the resultant electric field strength at that point being the vector sum, its magnitude will be less than the individual electric field strengths.
Can you reformulate your question regarding E=dv/dr? E is not proportional to v, it is it derivative in regards to space...
Hi @Physics Made Easy I find your videos both inspiring and educational, yet I feel the playlist on electricity went a little too off on the advanced side not explaining the basics thoroughly enough. Would you ever consider adding a few detailed videos on resistance, voltage, current, and basic circuits? Thank you
Hello James, thank you for your encouragement.
There is no real structure or plan in the playlists (playlists are not courses), I just categorize the videos in major subjects.
Still, when thinking of it, what you say is correct. Recently, I did tend to make videos about the topics I find inspiring, and thus, that can be of higher level (yet remaining within the scope of high school physics).
Your suggestion remains excellent though. thanks. I will consider this for future videos. Note that some of the older videos on that playlist do talk about circuit basics, but in a more applied and concise way.
Very clear and meaningful treatment of this topic. Thank you.
Thank you :-)
Hlo Sir, How come the position and momentum are independent variables in Hamiltonian mechanics? Consider SHM Hamiltonian when we change position , Momentum changes right?
Both are related to each other right?
Thank you
Hi Gowri,
I see with that question that you stepped your level a notch in physics. Like my real life students, my TH-cam students are growing up lol! It's so cute haha ;-)
I am more familiar with Lagrangian mechanics than Hamiltonian, but considering position and its time derivative (velocity, or momentum) being independent when solving the Euler Lagrangian equation, is the same than in Hamiltonian mechanics. And actually, I have the same question as you do. Why do we do that while intuitively, know x and v are dependent.
From my research on Internet, it appears to be linked to the approach taken. This dependence is actually what we are trying to find (a differential equation that can then easily provide a function of position with time).
So we start like if there was no dependence and see what happens...
When solving the EL equation at a given time, we do not have a known path for the least action integral: At any position can be associated any momentum and vice versa, which lists all the possible action paths. That is why we can initially consider these as independent, in order in the end to find their dependence! (which is actually solving the problem by finding the differential equation on position.)
I am not sure if I am clear (or even if my understanding is correct for that matter), but here are the links I found that could be of interest if you want to dig:
www.quora.com/Why-is-velocity-considered-to-be-independent-from-position-in-the-Lagrangian-formulation-of-Classical-Mechanics
www.physicsforums.com/threads/why-are-position-and-velocity-independent-variables-in-a-phase-space.883013/
physics.stackexchange.com/questions/168551/independence-of-position-and-velocity-in-lagrangian-from-the-point-of-view-of-ph#:~:text=Since%20Lagrangian%20is%20calculated%20at,velocity%20and%20position%20are%20independent.
You actually threw me out of my comfort zone with your question. Thanks! That’s the real fun of it, because it makes me progress too (a teacher is just an eternal student!)
Hello sir
Sir while explaining surface tension you mention that the surface tension acts along a line (boundary) , when the surface is flat. But what will we happen in the case of a sphere (curve surface), and if such things happen then , doesn't it will be on a single point of contact with surface of water???
Also sir as we know, earth is moving around the sun in an accelerated motion , so at every instant when earth changes its direction, why don't we feel inertia of direction, as the earth is moving with way high linear velocity???
Hi Kim,
Surface tension : In the case of a sphere, that would probably require a little calculus, where the variation variable could be the angle of the interface with the horizontal (or the distance from the center of a disc). In that case : the extension between water molecules will vary with the distance from the center to the extremities. You could imagine co-circular lines of iso-tension. If you average-sum all these surface tensions, due to each circle (considering mass variation too), you would get something inferior to a flat disc. That’s why a sphere will sink more. (Sharper the entrance to the water, more easily the object can sink.)
Rotational inertia : We actually do, but the effect is very small comapred to gravity. But if you consider the effect due Earth rotation instead, there the effect is significant : The apparent gravity at the equator is 9.78 m^2, and at the poles 9 .83 m/s^2 . Another effect of rotational inertia is the coriolis « force » (note that it’s not a force , but it appears so due to inertia, like the centrifugal force)
Really enjoy your videos.
I'm hoping your channel will progress into inductors, analog crossovers and perhaps even some acoustics.
Hi R,
Thank you for your kind comment.
Inductors: well, I wanted to do so but I have too much on my plate these days. These videos requires a lot of time to produce, a commodity I do not have in heaps! Yet, it's still on my list (along other topics) for when my busy agenda frees me again!
Hello sir
It's a short one,
We have always been told that the formula to calculate the angular displacement/theta is given as (l/r) but as a side note is given "only for small angles". Why it is so sir?
I guess because in the calculations that derive the formula, there must ne a point where you need to use the small angle approximation (where one assumes that sin (angle) = angle)). By using this, the formula obtained will only be reasonably accurate for small angles (usually less than around 10-15 degrees).
Sir I have one more confusion from sound. We are taught that the sound wave are longitudinal waves. And we convert them to the graph of pressure or density variation versus distance. the amplitude is defined as the maximum displacement of the particles, and for the sound waves maximum displacement of particles is horizontally ( left and right) . But still we denote the amplitude of sound as the maximum variation in pressure or density, even though the the si unit of amplitude is meter.
Please resolve this confusion sir.
Hi Kim, the Y axis of sine graph representing a longitudinal wave is not pressure or density, it is displacement versus the equilibrium point (that is Y = X - Xeq ). I have seen text books making the mistake you describe, or maybe not explaining clearly how they draw such density graph...
If you consider the positive direction for displacement (i.e. the positive direction of the Y axis) as being displaced to the right, the maximum density occurs on the x axis where the sine curve crosses the axis and has a negative gradient (at this point, particles to the left have a max displacement to the right, and particles to the right have a maximum displacement to the left, which leads to a maximal compression).
The same way, the rarefaction points are when the sine curve crosses the axis with a positive gradient. Think about it...
Hello!!! I love your point of view on explaining these physical terms, found it very helpful!! thx!! Having one interesting thought here, as you mentioned when we put a dielectric material into the capacitor, as which having a much higher permittivity (than air), it will requires more charge to be build to balance out the effect of the induced electric field. Now, as we increase the permittivity of the dielectric, more charges can be stored, to the point the permittivity is infinite (like a metal), what would happen, assuming we can have some sort of barrier to prevent the charge to go through the metal. are we creating a plasma here :)
Hi,
Interesting, but I see a problem with your reflection: you assume a barrier that you place to prevent charges from passing through the material of infinite permittivity (a metal). What you are doing here is creating two capacitors in series (the di-eletric used for both capacitors being the charge-blocking material)... That changes fundamentally the configuration you are trying to explore...
@@PhysicsMadeEasy Got u. thx!!
Wow this is briefly well explained !! thankss for this vid sir
Thank you, I am glad you enjoyed it.
I've never got this before, thanks a lot.
Sir I have another one, actually two,
First, sir in our homes there are plane mirror, and its very common. But sir when I touch the mirror surface still some gap is present between the virtual image and my image. I thought it was due to the width of the mirror but what is the actual reason sir?
Second sir ,the ropes that are present in our homes where we put cloths to dry , when left undisturbed why they bulges outward more from center as compare to other portions?
Hi (what's your first name?)
1/ the reflective part of a mirror is the thin metallic layer behind the glass. When you place a finger on the mirror, the gap you see is twice the thickness of that glass.
2/ What is instead of a rope you placed a metallic bar? It wouldn't bulge. The bulging of the rope is due to the material properties of that rope. more specifically how the bonds between molecules respond to external forces.
Sir, would you please explain the following?
Does free space and air that we are breathing mean the same thing ? How the permittivity changes between this two ?
Mathematically,i proved e(epsilon) for air is equal to e(epsilon_naught).
Iam really confused between this two. Hope i get cleared sir
P.s iam currently working on maxwell equation derivation sir
Hi sgiri. Compared to condensed matter (= solid or liquid material), air contains a very low concentration of molecules. Therefore, the effect of these molecules on the electric field will be minimal, barely significant when you compare with the effect of the huge amount of molecules in condensed matter.
Consequence of that: the ratio of the permittivity of air with that of vacuum is very close to one: 1.0006 to be exact.
Does this help?
@@PhysicsMadeEasy sure sir
It is very clear thanks for explaining !!
The end part of the video teaches me a lot. thank you
你好 little magic fairy. I am glad my work was useful to you :-)
Sir does circular instantaneous speed and linear instantaneous speed is 100 percent same or there is any difference between very small displacements on circular track and linear track?
Hello Rahul. angular speeds (what you call circular I suppose) and linear speeds are not the same thing. Linear speed (LS) is distance per unit time, angular speed (AS) is angle covered per unit time. The relation between them is the radius (LS = AS x R). This relation applies for both instantaneous or average speeds.
Sir I'm asking about instantaneous speed on circular track which is equal to omega ×radius in comparison with linear instantaneous speed
@@rahulkajala25 Imagine you would put a mass at the end of a rope, and spin it (no gravity, no air resistance: you are in space). The speed of the ball would be omega x R right? Suddenly the rope is cut ... What would be the speed and direction of the motion of the mass after that event, still the same (there is no acceleration anymore, so V = Omega x R). and the motion would be linear.
In other words, the speed of the ball perpendicular to the radius (what you call instantaneous speed on circular track) and linear speed are the same concept.
Could you please make a video on inductors and energy storage/transmission involved?
Hi Chinmay, thanks for the suggestion. I'll keep it in mind.
Hello sir i have a little question.
Why does the size of the image(everything) gets smaller and smaller than the object , when object is placed between two parallel mirrors?
Hi Kim.
Because the object has a virtual distance to the mirror that increases after each reflection.
Thank you sir ,😅
What an amazing class sir you made it so easy for me and saves my lot of time
Hello Mahen, Thank you for your kind comment. I am glad my work helped you!
Sir I have two more questions
1) Sir suppose we want to find the work done and given is that force (f) is a function of displacement (s) as f(s)=f=s². So integration should be done from 0 to s , and I did and got s³/3.But sir if want to find the final velocity (v) than can we equate the W to 0.5mv². I was confused because it's for uniform form force and here it is variable. And if not then how can it be found sir?
Time
2) sir suppose we have a Blok of mass m in the air(but no drag) at height h, so gravitational force acting on it is mg. Now we apply a force of equal magnitude but in opposite direction to balance the forces. Show the block will either be at rest or it will moving with a constant velocity. And here I assumed it to be going with uniform velocity in downward direction and covered the height h. Now both the forces are still acting so there must be some work done by them: for the gravity mgh and for the external force -mgh. So there is net Work done 0 and so it doesn't accelerate. But while approaching downward is potential energy decreases, and my question is where that potential energy lose? Please explain sir
Hi Kim,
1/ Because Energy is a conserved quantity. The way the object got it (with a constant force or not) does not matter… The work done by the force resulted in some energy provided to the object. If that energy goes fully to the object as KE, then that KE will be equal to the work done (s^3/3). You can write W = s^3/3 = 0.5mv(final)^2.
2/ We will suppose on a planet with no atmosphere (no air).
How would you apply that force? You would need a flying vehicle with a rope holding the object so that tension in the rope would balance the force of gravity. How would you keep the vehicle from accelerating downwards… (make it fall at a constant speed), You would need to use energy (propulsion upwards just enough to counter grav. acceleration). … I let you finish the reasoning 😉
Sir I want to know from you that why magnetic lines of force form closed loops and what is the logic behind the fact that outside magnet they originate from north pole and terminate at south pole whereas inside the magnet they start from south and end at north pole .
Hello Shadma. In classical physics, a field is continuous. The consequence is that the field lines must be continuous, this is why these must be closed loops. And this is also why when a field line enters a south pole it continues to the North.
@Physics Made Easy hello sir, as you have recommended to search for state functions and I did but I find something very confusing. In almost every video it was said that heat and work done are the two most common examples which are not state variables or state function. It means that while doing work, the work depends on the path of the object that it took and it seems obvious because the formula itself is force into displacement. But sir it was also taught work done by a gravitational field on an object does not depend on its path. So it is also state function because it fits in the definition of the state function. Is it so sir?
I have one more confusion related to this, whenever there is a situation in which it is given that an object of mass m is lifted by someone, so we take that the force applied to lift the object is MG , this means that the object is moving upward with a constant velocity but what if the force applied is not mg?
Why we always take MG in this type of scenario sir even though it is not always ?
Hi Kim, Work and heat are not state functions because these are energy transfers not energy states… You change the state of an object by heating it or working on it.
For example consider hunger as a state function. Weather you eat bananas or rice your hunger will become small. And whether you eat your portion fast or slowly, your hunger state will be the same at the end of your feast.
Your second question. When you apply a force equal to mg for a height from 0 to h, it means you provide work equal to mgh. Because the net force is balanced, there is no net acceleration, so no increase in speed, so no increase in KE. All the work you did went into PE, which is therefore mgh.
If your force is > than mg, the object will accelerate so the KE will increase. Your work Fapplied*h will contribute both to the PE and the KE.
I hope this helps
Enjpy the year end celebrations!
@@PhysicsMadeEasy Thanks for this explanation sir.
I request you to make many more awesome conceptual videos like this regarding electromagnetism. We cannot grab the concepts by merely looking at the books though we are graduate students. 🙏🙏
I would like to, but too many things on my plate right are interfering with my TH-cam activities ...
You are 100% correct regarding how to learn things: Reading books is not enough, you need to reflect on the notions you encounter and compare your understanding with others (for example reknown TH-cam videos). Then, don't forget to train that knowledge with exercises and problems ;-)
Hello sir!
I am in one more confusion,
Sir the formula of kinetic energy, 0.5(mv²), works when the force acting on a body is constant , as while deriving this equation when used equations of motion. And if the force is variable we can take the help of calculus.
But sir when ever we examine a problem in which mass, say m, and its velocity , say v, is given we blindly apply the above formula to calculate its kinetic energy.
I suppose, that the value of K.E we just get is the work we have done on a body with mass m, initially at rest, and to bring it to velocity v, with a constant force.
This is my main doubt, that when we have this scenario we don't know whether the body has acquired that velocity with a constant force , though we do this. Isn't it very uncanny sir?
Hi Kim,
Because Energy is a state function: the energy of an object does not depend on how it got it, it only depends on the state of the object at the present time. Google up ‘State Function’ to know more 😊 !
@@PhysicsMadeEasy hello sir, as you have recommended to search for state functions and I did but I find something very confusing. In almost every video it was said that heat and work done are the two most common examples which are not state variables or state function. It means that while doing work, the work depends on the path of the object that it took and it seems obvious because the formula itself is force into displacement. But sir it was also taught work done by a gravitational field on an object does not depend on its path. So it is also state function because it fits in the definition of the state function. Is it so sir?
I have one more confusion related to this, whenever there is a situation in which it is given that an object of mass m is lifted by someone, so we take that the force applied to lift the object is MG , this means that the object is moving upward with a constant velocity but what if the force applied is not mg?
Why we always take MG in this type of scenario sir even though it is not always ?
Sir I have one more from your previous video about why the gravitational potential energy is negative .
I got confused when you said that you were choosing the scale. You had chosen the scale in such way that the force applied by us is positive, but what if we reverse the scale, in that case force applied by us is negative and on further calculation the gravitational potential energy is coming positive.
Where I am wrong sir?
Hi Kim, if you reverse the direction of the scale, you change the sign of the force, but you also change the sign of the displacement... ;-)
@@PhysicsMadeEasy yes sir thank you 😀
It is always good to watch your videos.
Thank you Bijoy. I am glad you enjoy them!
Sir I have question about tension, sir we always consider a string to be massless because that implies that the tension force is acting uniformly throughout the string but sir when it comes to a string that have mass , it is said that the tension force will not be uniform. Moreover the tension force will be maximum at the end where the force is applied and it will be least at the free end. But sir no one give me the reason for this scenario why it happens ?please explain this, because sir considering a string to be massless is equivalent to considering gravitational force as repulsive because if there is a matter it should have some mass? Won't it affect the result?
Hey (what is your first name?),
Strings are considered massless because it simplifies grandly calculations: You can consider the string like a single system when you draw a Free body diagram. If it is not, you need to consider the strings like a set of tiny systems of length dx in order to describe accurately the system. Usually the mass of the string is small compared to the mass of the thing that hangs from it, so it is reasonable to neglect it.
Now to your question, I’ve been thinking about it. I do not have a straight forward answer, but if did dive into it, that is the model I would use to start working on it:
Consider a string made of one single massive particle and attach it to two walls with strictly massless rigid bonds. Do a FBD on it and derive the forces (direction and magnitude)
Now, consider three particles instead of one (the bonds between the particles remain massless and rigid). Do a FBD on all of them and derive the forces.
Repeat with 5, 7 … N where N is an odd number
From this work, you should be able to generalize tension as a function of position.
@@PhysicsMadeEasy yes sir , tension will be maximum at joints and minimum at middle
Amazing video, great way of explaining things, thankyou very much
You are welcome Rawan, I am glad you enjoy my pedagogy.
Many thanks indeed! Wonderful explanation.
Merci Muhammad. I am glad you enjoyed it!
Nice video and presentation.
Dielectric is something that pass (permits) electric (charge) into a space occupied by it.
We know that vacuum-space holds electrostatic, so itself is also a dielectric, the size of a universe.
As it permits electric into the vacuum-space, it also responsible for light propagation within the vacuum-space.
Further?
Vacuum-space is a dielectric with no physical but electrical properties, permittivity, known as e0 or Aether.
So light from distance stars can reach us because of e0 or Aether.
Hi there philoso,
First, a dielectric lets the effect of a charge (the electric field it generates) pass through it, not the charge itself.
And yes, you can say that because vacuum has a dielectric property (eps 0), light, which is basically the propagation of an oscillating electric field, can pass through it. And yes again, that is why we can see the stars at night.
@@PhysicsMadeEasyFirst, no one said about “pass through”
Incredible explanation! I hope you keep creating content
Thank you so much for your kind words! I am glad you enjoy what I do.
I will keep creating content, that's for sure, it's a hobby, but as all hobbies it need to be at a suitable pace ;-).
Bonjour (hi) sir....
I have one doubt in dipole moment....
Dipole moment will happen when electric field passed through it????? Can you pls reply sir...
Sir, explain us what is semi cunductors and how we use in gps
Semiconductors is just a type of material that conducts electricity in certain conditions and not in others. to explain how it works, there are quite some notions to introduce like band diagrams and doping, it's more for a video than a comment, so I keep your suggestion in mind :-)
Sir I have a question is that,in the sun core nuclear fusion occured and it emits highly energetic radiation called Gama rays. So it emits gamma rays but we get UV rays how's that possible.sir explain us clearly
Hi Shivam, indeed gamma rays are produced in large quantities in the Sun's core... but in order for these to reach out, they need to leave the core and go through all the other non fusionning layers of the sun. By doing so, they collide with a lot of matter which results in the ray losing its energy and the production of lower energy photons. hundreds of thousand of years later, when it finally reaches the surface, the gamma ray is a not gamma ray anymore because it lost a lot of energy in that process.
As for the UV light, it's another phenomena: Black body radiation. Close UV (the one you are referring too I suppose), is the end tail of the spectra (around 200nm). Much hotter stars than the sun emit a much higher density of UV light. I wouldn't enjoy living on a planet around such a star!
It means, sun ray take alot of time to reach us,omg😲😲😲😲
Hello sir I am Kim, i have more and it is about surface tension. Sir the definition of surface tension is given as force acting on a unit length perpendicular to it. But sir consider a blade, though the blade is denser than the water , if we gently put it on the surface it will float. Sir here water particles are attracting the blade particles through out the surface, but surface tension is N/m ( N/m²). I feel it very awkward because , in questions also we are said to take the boundary (perimeter) of materials, not the area of contact with water. Sir please clear this?
One more ( Diwali 🎁), sir in calculating friction force we just use normal reaction and coefficient of friction. Sir but in daily life (from my frame of reference) it seems to be also dependent on the velocity. For example, at garage , when the grinding machine is used , that spin at high velocity, the sparks come out , but if it had spun slowly nothing happens. Why sir?
Also sir it is said that the static friction is greater than kinetic friction because while moving the irregularities don't interlock perfectly as compared to when they are in static state. It means that at much higher velocity irregularities won't be able to interlock perfectly, as they would directly jump on to the next portion. It means that at extremely high velocity is the friction should decreased to a large extend but it don't happens? Why sir??
Also sir, the composition of atmosphere tell such that in what percentage certain amount of gas is; for example nitrogen 78%. But sir my question is that which quantity does this percentage indicate, first time thought it to be volume but sir as we know air is a homogeneous mixture, so volume of each gas should be the same. So my question is which quantity does it represent whether it is moles or in the terms of mass?
Please sir...
Hi Kim,
1/ I encourage you to revisit your understanding of surface tension. Surface tension is a property of the interface related to the amount of intramolecular forces that occur between water molecules along a line S = F/l. These forces are larger at the interface than in the bulk.
Once you place an object on the surface, the distance between molecules of water will extend, and like a spring generate an extra return force. The direction of the force will also change gaining a vertical component. That vertical component compensates for the weight of the object. The object appears to be floating. Visualise it: Naturally, the extension of the surfacic bonds between water molecules only occur at the perimeter (assuming the surface of the object is flat).
2/ You are confusing energy and force… P = fv. For the same amount of friction (f), with a larger speed v, you will dissipate energy at a larger rate (P)… hence the heating and the sparks.
3/ Usually, the composition of the atmosphere is provided in ppmv (parts per million in volume). It’s more intuitive because in normal conditions, the volume of one mole is the same whatever the gaz. If you know the molar masses, converting to the the mass fractions is easy.
Sir I have a question.
If there is a slant surface and there is a conical solid, then why the surface with larger radius points downwards.?
Hi Kim, your question is a little out of my field of expertise. For me it makes sense and would be in relation with the angles formed between the normal between the intersecting plane and the surface areas of the cone at all points. But I do not know how to prove this mathematically. You should ask your Math teacher!
Hello sir ,
I have some confusions.
1.) Sir I have observed that in almost all the water taps I have seen , there is a strange pattern. First when the tap is opened partially or very little , a laminar flow of water is observed but then turbulent flow is observed when th tap is opened completely. But the odd thing is that pattern I turbulent flow is observed repeatedly, meaning the next when we have done the same the same pattern of turbulent flow appears like one end it is thinner or any thing else. Is that pattern is predefined?
2.) Sir whenever I see bubbles or foam I any liquid, whether water or milk, the bubbles gradually move towards the boundaries of the glass or containers
. Why it is so?
3.) Also sir when a bubble is formed on the surface of transparent liquid, then the light intensity at bottom of that bubble increase. Why this happens sir ? Is it acting like a lense?
Hi Kim,
Question 1: I do not understand your question. Please reformulate.
Question 2: To minimise surfacic energy.
Question 3: Yes, there will be refraction occurring when light passes through the bubbles surfacic layer. Under the right conditions, it could act like a lens. It can also act like a thin film with constructive or destructive interference depending on the wavelength, incident angle and thickness of the bubble surface. This is why soap bubbles can look all iridiscent, and when they thin out, they lose this iridescence and become all transparent.
Thank you sir🙏..... You really made it very easy to understand ❤
You are welcome Devansh. I am glad I was able to help!
Managed to explain something that took 3 lessons in 10 minutes. Thank you.
Hi Somebody ! Thanks for appreciating my sense of synthesis :-)!
When he said she application of the phenomena, he got me hooked ☆
Thanks a lot Sir!!! You really taught me exactly what i needed to connect the dots from my notes. Jai Shri Ram
Super! Thank you Jai for your feedback: the effect this video had on you summarizes exactly the reason why the Physics Made Easy channel exists!
You explains very nicely with animations :)
Thank you for your kind words.
Thankyou sir. This video is very useful for me
Thank u so much... you r the best
Dear sir,
Please have a read through sir.
You are amazing at the explanation of concepts through logical reasoning. Please 🥺🥺 have a look at this sir.
Would you please take separate lecture on the following topics via online media ? I will separately pay for you
Iam barely in need of topics in optics mainly michaelson interferometer and how circular, localised and unlocalised fringes are exactly they are formed ? How it naturally leads to the formation of the alternate bright and dark fringes ? Who on earth ordered light to do so ?(when I search for answers,it gives that it is due to the fact of phase and path differences between the waves), but why this is the case ? When I looked up articles that discusses interferometer mainly michaelson interferometer, I found another interesting topic called michaelson Morley experiment and it is one of the famous experiments which disproves the presence of ether in the atmosphere. Is this is the same principle applied with interferometer ? What is the connection between formation of fringes and the presence of ether in atmosphere. Please consider and take classes for me. I am only dependent on you sir. If you take classes for me😊, i will so happy sir
Hi Sgiri, thanks for your message.
If you are searching for a tuition from me (high school physics, IB, AL and AP1), it might still be possible. Check my tutoring website www.physics-tutor.nl/ and write to me through the website after looking at the tuition conditions.
About your question. Try to look at the theory related to waves first before looking directly into an application. The fringes are called fringes of interference. Take a sine curve, copy it, then shift the copy by a half wavelength. This creates phase shift of pi between the two waves. Add the two together, and the result will be a flat line. If the sine curves were light, you would get darkness as a result.
An interferometer takes a ray of light, generates a reflection, and adds the reflection to the original beam. The difference of distance travelled between the original and reflected ray (called path difference) will have an impact on the resulting wave. This is how one can detect extremely small differences of distances (like the LIGO interferometer measuring the tiny distortions of space time due to a fusion of black holes billions of light years away).
But first forget about the interforemeter and familiarise yourself to the phenomena of interference with a good textbook. A good start is to look at how 2 slit diffraction works. Your questions shows that you first need to clarify this.
Good luck !
@@PhysicsMadeEasy sir,once I got clarified with this I will tell you. Thanks sir. I need separate tutorial on that Michealson interferometer. I will make sure to familiarise in the ocean of interference
Do this dielectric when heated evaporate and stranger odor smell?
Happy New Year sir , I am in one more trouble.
Sir the law of reflection states that the angle of incidence is equals to angle of reflection. This is said to be applicable with all types of mirror whether it is plane mirror concave mirror or convex mirror.
And also when we draw a radius (of any circle), it is perpendicular to the tangent to that point so it acts a lot like a normal for a Mirrors. But my confusion is with one of the rules of concave mirror which is stated as if the incident ray is parallel to the principal Axis then the reflected ray will pass through the focus of the circle ,which is Halfway between the pole and the centre(of a concave mirror). But when I have drawn a concave mirror with Centre C and Pole P and focus F and taken and line l parallel to CP(radius) and let the point where it touches the mirror be O. So when we connect C and O, CO should be the normal which means that the angle between CO and the parallel line(incidence ray) should be equal to the angle between CO and the reflected ray, so when I have done so I found many times that it is not passing from Focus .The line which passes through the focus does not have the same and angle as the incidence angle.
Where am I going wrong sir I have tried it many times and all the times I am getting the same result.
Please clear this confusion sir ???...
Oh, Kim, you are always in trouble 😉
What you are experiencing is called spherical aberration. The rule that rays parallel to the principal axis will focus on a single point is true for parabolic mirrors, but not for spherical ones (like a concave mirror). It is approximated true for spherical mirrors when the radius is large compared to the size of the mirror itself, i.e. for a small aperture.
Check this link : it has a great picture that explains it all :
phys.libretexts.org/Bookshelves/University_Physics/Book%3A_University_Physics_(OpenStax)/University_Physics_III_-_Optics_and_Modern_Physics_(OpenStax)/02%3A_Geometric_Optics_and_Image_Formation/2.03%3A_Spherical_Mirrors
@@PhysicsMadeEasy thank you sir
Thanks for everything you do and teach me dude like your videos are the best way to find a source thanks for everything keep it up and keep posting these kind of videos thanks bye :D🙂
Thank you Alex for your kind comment. I am glad you can use my videos as a starting point to dig a little deeper. It's the whole idea behind this channel: Help students grow their own wings! :-)
I don’t know how you don’t have a million subs. I have a question. What does alternative current mean? Thanks
Hello Arnav, Thank you for the kind wish... Millions of subscriber, maybe , I should be careful for what I wish for haha: How could I keep on answering all comments / questions haha!
Direct currents: electric charges move always in the same direction. Alternative current: they oscillate around a central point (they go back and forth in a cable). They do so because the voltage oscillates too (they are continuously pushed one way, then the other)
Really very good lecture proffesor.
Thank you for your kind feedback Tayyab.
Outstanding!
thank for your explanation professor
You are welcome Fahru, I am glad you found it useful.
Totally awesome Sir...
Thank you for your kind words Ritu.
6:07 water polarization in electric field… what happens if it was in magnetic field?
Hi Fi, Here's a starting point for that question: www.sciencedirect.com/science/article/pii/S2211379717317230#:~:text=Highlights&text=Proper%20use%20of%20magnetic%20field,change%20the%20properties%20of%20water.&text=The%20evaporation%20amount%20of%20water%20increase%2038.98%25%20after%20magnetization.&text=The%20specific%20heat%20and%20boiling%20point%20of%20water%20decrease%20after%20magnetization.
What does partial charge mean?
I enjoy physics but sometimes I start questioning myself" Am I studying it the right way?" " Can I explain physics in my own words or even my own mother tongue?". These questions sometimes even disturb my sleep. Sir please once say that "Physics is all about understanding and application and not rote memorisation"
Absolutely Sandeep. Actually, you should look at the pinned video presenting the channel which confirms your thoughts on the subject. If you can explain rigorously a concept with your own words, it is a proof you actually understand deeply the concept, and thus know how it fits in the big scheme, as well as reflect on applications.
But, do not let this disturb your sleep... ;-)
@@PhysicsMadeEasy thank you so much sir and I now promise I would think more deeply about physics concepts and not hesitate to explain it in layman. PHYSICS IS AN ADVENTURE
I would be interested in how this concept applies to human biology. Are we dielectric? If so, do radio frequency fields and EMFs change our bodies? Anyways, thank you very much for the video and the others. They are very well done and I will keep plumbing through them for insight.
Hi Mike,
Yes, because we are mainly made of water but the effect is minuscule, properly insignificant, compared to the random motion due for example to temperature. For a significant effect, the intensity of EM waves would need to be huge. btw, the light from the sun is also an electromagnetic wave...
And thank you for your kind words :-).
hello teacher! Very cool, I really liked it. May I translate your videos into Kazakh and put them on TH-cam?
If my work can help students in Kazakhstan, Sure! Please refer to this channel in the video, and in the description. Let me know how this goes. I love to see how the human fascination for how our universe works, has no cultural nor physical borders :-)!
U made it so simple thank u
Physics is easy!
Sir your videos are best on TH-cam ...
Litterly I am studying. In class 10 but I watch your videos and clear my concepts..... Thanks sir ....
Hi Mamata. Thank you for your kind comment. I am happy my videos help you clarify things :-) Good luck with your studies (imho, the real physics fun starts in Grade 11 !)
Well-made explanation , thanks so much
You are welcome DH, I am glad you enjoyed my work :-)
sir what question do science or physics ask to nature like do physics ask why things happen or how things happen or both or something else ? what is physics..................
Ahh a philosophical question :-). imho, Physics attempts to explain the how, not the original why... Many (non scientific) people oppose science and religion, but in truth, when you study and understand physics in depth and realise the amazing beauty of how things work, it can fill you with awe. Result: more than half of the scientific community beleives in some form of higher power or deity.
(PS: And I am saying this as a non beleiver! Meaning I do understand why so many believe,and respect their belief)
can you explain why asking " why " does not make sense or give your detailed views on this in any ways you comfortable with video or reply or shorts or any thing . i would love to know 😌
@Physics Made Easy can we explain the cause or reason of any property of anything
@@x5dot No we can't... For example, we were able to retrace back to the big bang, but we do not know really what caused it... There are lot of ideas and theories about that, and one day, we might find out. But we'll again wonder from where what caused the big bang came from in the first place. And this can go on forever, in an infinte cycle, where a new discovery ends up with a new question...
@Physics Made Easy thank you Sir 😊
thank you, for making an amazing video
You are welcome Rafay
I watched your video why gravitational potential energy is negative. Can it be < when we displace a body from the surface of the earth , we do some work which is stored in its potential energy. Since the force of attraction is towards the centre of the earth and the displacement is outwards the centre of earth so the work done will be negative as the gravitational force . so will will be negative and so the Potential energy will also be ZERO.
Hi
The work done is positive: in W = F x D, F is the force applied on the object to move that object, not the force of gravity (it is opposite to gravity). F and D are both in the same direction.
The PE becomes then less negative... (It is zero when both objects are infinitely apart).
thanks so much! really this video helps me too much.
Hello Alaa, I am glad my work helped!
Really good, thank you!
You are welcome Chi :-)
❤❤❤❤❤i enjoyed it very much❤❤❤❤❤
❤️❤️❤️❤️
Thank you very much...the dipole has always been a scary topic for me.
Also sir, is it possible for you to activate Super Thanks? so that people would be able to support the channel?
You see Tirthankar, dipoles are not that scary after all ;-)
Thank you very much for your suggestion, I didn't even this feature existed! I just activated it.
Felicitations. Vous fournissez un superbe travail. Grace a vous il me sont deja clairs certaines notions fondamentales. Si vous pouviez Donner une explication comment les Ovnis peuvent Faire des virages a 90 degres sans ecrabouiller l^еquipage en manipulant lespace-temps....
Haha, je crois que si j'avais la réponse à cette question, j'aurai déjà construit et breveté le moteur correspondant ! Et serais probablement richissime !
Good stuff 👍