Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory. Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion. Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html I also request H C Verma sir to review and comment if any error.
I do not fully agree with this explanation.. According to me: Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Only from the Master himself can we get such a masterpiece ... many people have talent in the subject but very few have the talent to make people understand ... Tons of respect Sir . You can make a child understand physics
@@bibhutibhusanpradhan527 yeah u r right but everyone can't be Einstein ! Most of us need a guide to show us correct path , but our system is just making money!
When I was in +2, I feared physics. Someone suggested me your book, I bought it. Today I am a passionate IITJEE physics faculty. Sir, this is how you impacted me.
@@thecurrentaffairs7962 the easiest thing in the world is to judge someone which requires little / no brains. If you see the video properly, sir gave an analogy to understand the concept better. It has got more to do with the scope of audience. One has to go into the depths of Huygen's theory and Maxwell's equations to exactly understand the phenomenon of bending of light in refraction. I am very sure that sir could easily explain that, but again it goes back to the same question - "scope of audience". Sir is sharing videos for secondary and Sr secondary school. Sir used the analogy of car and rough road to explain how the phenomenon takes place. And the comment I made is not just pertaining to this video, I have gone through the concepts of physics and it has influenced me a lot. And coming to my physics knowledge, I don't mind someone calling me weak.... I only make sure that the slope of my learning curve is always positive.
I always explained this to my students before they even asked and whenever I gave a similar example they would say "wow" ❤️. The best moment for a teacher !
From Snell's law: sini / sinr = n2/n1 = a constant, where n1and n2 are the refractive index of first and second medium respectively. When light rays travel at some angle in one medium and goes into the other medium, the ratio of their refractive index remain constant so the ratio sini / sinr is also a constant. Hence, the angle of incidence 'i' and the angle of refraction 'r' would be different. That is why, light ray bends when goes from one media to other media. This can also be explained on the basis of wave theory of light that may be a bit confusing for students below class XII.
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
@@finisherx4108 Sir gave an analogy not an explanation... Question is asked by a class 10 students..he can't explain Maxwell equation to him at this level.
Sir this is the first time I have visited your channel and just within a minute of watching , your persona has started to impact me. Your books are undoubtedly amazing but today your personality and humble nature have also proved to be amazing and superrrr inspirational! Your videos have compelled me to change my perspective of looking at physics. Thank you so much sir , you're a gem!!!!!
For those who want to know more about it try to study huygen's principle . It was definitely wonderfully explained by Sir with an example . But you will get more feel or understanding if you specifically are looking for behavIour of light . Thanks
This kind of explanation is also given in S. Chand book of physics for class 10, and they have also tried to explain in somewhat similar passion. But HC Verma Sir Explained it more properly, that's why he is the best.👍🏻
*Indian teacher : how dare you to ask such stupid questions that can't be asked in your so called prestigious board exam.* *HC Verma : This new generation made for innovation and that's why this channel make themselves innovative.*
@krishna...pls don't use Indian teacher. Our country is famous for Guru culture. " This que ll not be asked in exm" is told by many teachers who don't know the answer. This not only happens in india but in many countries their education system having problem like India presently having.( Reasons for this is many...mainly bcz of politicians) so.... please..
@YASH MALIK defending..!!??😃 Fr your kind info, I m a teacher.i never said this to my students till now. I even say u can ask out of syllabus, subject related silly questions also. I fixed it. Many are doing. I think u misunderstood my reply.
@@akshaysekar355 Yeah you are right but I was saying some teachers are just teaching for marks. They want 1st rank in class but not everyone can be there. I want them to appreciate the child even when they score above 94% but they appreciate only to 1st rank holder. So sad.😞
If we understand refraction through Huygen's wave theory of light, then we can clearly understand why the light is bending in a optically denser medium....that car example is an easier version of that only....nicely explained...thank u sir...😀
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory. Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion. Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html I also request H C Verma sir to review and comment if any error.
@@satyabachan8164 this one is correct version ...but the issue is if you are telling this to a normal board student it will fly over the head ...hence h.c . Verma sir version
After getting this answer my mind just say this wow ! Just wow it was so overwhelming can't explain ... Teachers have huge role in making physics more interesting....
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
This is the best explanation ever!!! Thank you sir very much! I had this doubt for so long and no one was able to teach it to me! I dont know why I didn't look at it this way. I am blessed to have stumbled upon this video and thankful to the person who asked this question!!!
Here a Graduate Physicist. I left here an additional very simple proof of this using the conservation of momentum of photons, for the ones who want to know more :) If in medium 1 the index of refraction is n1 and in medium 2 the index of refraction is n2 and for the definition of index of refractions and wavelength we have: n1 = c / v1 , v1 = λ1 * f n2 = c / v2 , v2 = λ2 * f Dividing the above equations we obtain: n2 / n1 = λ1 /λ2 So if n2 is higher than n1, the wavelength in medium 2 is smaller than in medium 1. Now because the photon momentum is: p = h / λ Applying the conservation of momentum of the incident and transmitted photon along the parallel line of medium separation: p1 = p2 → h/λ1 *sin(θ1) = h/λ2 *sin(θ2) → n1 *sin(θ1) = n2 *sin(θ2) This is the Snell Law!! So the light bending is just a consequence of the conservation of momentum of photons!
But how can you even apply conservation of momentum in parallel direction only but not in incident (normal to surface direction)....and why momentum of conserivation is applied when the photons expierence boundary resistance force upon entering the next medium i.e conservation law not valid...correct me if i am wrong
@@cricobug9778 Very good question! In the perpendicular direction the momentum is not conserved between the photons because the photons are exerting a perpendicular force in the material! This phenomena is called radiation pressure and for example it's what makes solar sails to work. Because no force is exerted in the parallel line of medium separation the photon momentum must be conserved along that direction. This is analogous to a ball bouncing on the floor, the momentum of the ball is only conserved in the parallel line of the floor.
HC Verma Sir is different from the classical mold of teachers...he never disregards even a seemingly simple question such as this. I loved this analogy, its a new angle of thinking. Of course, it seemingly simplifies Huygens Principle to a greater extent.
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
@@thecurrentaffairs7962 read the room. This video was not directed towards physics graduates but to a school student. So don't try to act smarter than a legend😑
@@jakeperalta8421 school students study about dielectric medium and the decrease of electric field in dielectric medium. It is not meant for kindergarten
have never enjoyed the basic physics of life before. Thank you so much sir for starting this channel and been the Go To encyclopedia accessible for all the curious minds.
Sir, You're an inspiration to all of us. Your examples and approach to topics, it's all just simplified in a better manner! Concept of Physics has really helped me learn physics in a fun, more applicative and a beautiful conceptual interpretation. Thank you so much Sir!
I too question this in std 9. I came to know the ans in class 12 after reading optics chapter. But this man uses easiest way to explain that even a non science student can understand
Answer is not given in 12th. And answer is not in optics. Its in ELECTROSTATICS. Plz get ur facts correct I hv written then answer in one of the comments
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory. Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion. Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html I also request H C Verma sir to review and comment if any error.
Sir, I'm preparing for Jee mains and all I wanted to know before my preparation is how to get an idea on basics and fundamentals. And also I wanted to know that how to get full grip on physics
Interstingly, a question was asked in JEE Advanced 2023 on the exact same concept, and it was a very beautiful question indeed. It was that should light bend or not on normal incidence while refracting through a variable density glass slab and the very first thing clicked in my mind was, oh, maybe lets try using the Huygen's Wave Theory and draw some wavefronts, and it worked like a charm.
There is a simple proof of this in the NCERT Book. In easy words it is because it bends so much thar it reflects. In the sense of the car as described in the video I can say that the car turns so much that it is equivalent to talking a U-turn hence it reflects back
@@naveenmeena1832 light photons give their energy to electron of refracting material . These electrons transfer their energies in the forms of reflected and refracted rays. Only few near surface electrons are able to produce reflecting rays hence reflection is just 4 to 5 percent
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Sir i had a doubt that when a light ray incident normally on a interface of any two different mediam then is there any change in velocity before and after refraction ? Iam asking this because when the medium is changing no.of particals also change so there will be change in velocity
Yes the speed change. Becoz speed of light is E/B The electric field vector of light decreases when it enters di electric medium such as glass or water
bhai mereko bhi smajhao iam in class 10th ye toh pta hai ki light bend hoti hai jo optically rarer to optically denser mai jaati hai pr ye wave theory kya hai
Let me solve this = when coming light make right angle with denser medium. ( one more thing i want to add why we call a medium denser because it have more number of particles ) these particles are always moving . So when bunch of rays or i mean light comes with right angle one particle of denser medium first introduse with any one of ray. But other one rays are still moving with that speed. Because they are not still interact with any particle (distance between particle must) so and after fraction second second ray also interact with a particle of second medium now easliy you can see. When you jion both ends path of light band. Its solve. 😊 i fill happy if this help you buddy.
mainly due to the attraction to the centre of the galaxy. a lot of galaxies have a black hole as their core, and all the particles of the galaxy tend to follow a spiral-like trajectory which is basically orbital movement around an object of high mass
Very nicely explained sir with such an easy example! Sir has proven that only great teachers make concepts easy for their students! How many of u all agree with this?
Sir there is ques . That when reflection happens , there also refraction bcz it is entering from one medium to another but rather we say it is a reflection ..... Two medium for mirror are air and glass throw which it enters and reflected by the coating backside , so why here we say it is reflection but it can be refraction toooo ...
sir H C verma light photons can travel in a curve path (minimum time interval) under influence of strong gravity field or acceleration field why light bends under medium ? or simply slow its speed it's hard to differentiate between two speed of light reduces in water by constant factor but how water molecues reduce speed of photon ?? whereas size of photons are much smaller than molecules is any correct models is available??? car model is not working ..
Diffraction is bending around corners of an opaque obstacle and for observable bending dimension of obstacle(e.g. slit width or hole diameter etc) should be of d order of wavelength of light.
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory. Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion. Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html I also request H C Verma sir to review and comment if any error.
When i searched this question on TH-cam i didn't expect a clear answer but when i saw that sir has made a video about this my face immediately turned like this😃
You are my idol sir.....🙏🙏🙏🙏i am using your book and my all concept are becoming strong and strong day by day.....Thank you soooooo much sirrrrr guru 🙏🙏🙏
We are very blessed to be born in such a era of this digital world Generally the offline teachers don't behave in very good way when they hear such type of questions from us but now the Online teachers try their best to clarify the actual phenomenon working behind our so called notes which the early age of people used to rote in their times. Thank You sir and all other teachers who have tried to clarify the tough concepts in very possible easy way
I had this question since class 8 but no one's answer was good enough forget about satisfying. So I forcefully stopped thinking about it until this day.Now I'm completely satisfied.Thanks to you sir.
To know the answer of this q. We have to know THE FERMATS PRINCIPLE OF LEAST TIME. *Light is a hurry.* With the help of this we also able to prove Law of Reflection (i=r)
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory. Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion. Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html I also request H C Verma sir to review and comment if any error.
Thankyou so much Sir. I also had doubt since my childhood days. I asked many teachers and also referred several books but I didn't get satisfactory answer which I have got now. Thankyou so so much Sir. You a true Gem of India
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Guys we are seeing this universe but if we go in quantum level then we saw that there is pure energy then why everything look like made up of particles?
physics has not come out of the egg. When it will break the shell ,then you will see everything in terms of energy and information. So till then just look at the egg. One more thing..when physics will reach its childhood stage ,biology will be in its fertility state
I almost cried after he gave answer in simple way with example.
Why man?
@@RaviKant-ey8yp Correct question..
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion.
Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html
I also request H C Verma sir to review and comment if any error.
I do not fully agree with this explanation..
According to me: Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
@@Concefacts The Space folds while traveling light
am I correct??
I always have such questions but teachers ignore them saying, "ye exam me nahi aayega".
LOL. How could some teacher be like that!
@@dimlighty 99.99 teacher is like that in india
*😆😆😆😆😆😆...I have also had such teacher when I was in school.*
@@PUBGgamer-kf5vz And the remaining 0.01% include HC verma sir
Most of the teachers in india only teach students about 2,3 and 5 marks questions of numerous kinds of examinations....
Im blessed to have been born during the digital revolution of amazing teachers like you sir💕🔥
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Only from the Master himself can we get such a masterpiece ... many people have talent in the subject but very few have the talent to make people understand ... Tons of respect Sir . You can make a child understand physics
I have the same question but teachers always avoid these kind of question 😭
and thats why india is not doveloping with the speed it should be
Most of the teachers are just dummies than professors
Well instead of cussing teachers we should question our intuition I don't think Einstein needed his teachers to answer this type of questions.
India is not developing for playing the blame game .
@@bibhutibhusanpradhan527 yeah u r right but everyone can't be Einstein ! Most of us need a guide to show us correct path , but our system is just making money!
When I was in +2, I feared physics. Someone suggested me your book, I bought it.
Today I am a passionate IITJEE physics faculty. Sir, this is how you impacted me.
That's great sir
Btw in which institute do you teach sir?
@@kyusiv9026 my last institute was Aspire IIT MEDICAL, Shimla
If u are really a good teacher u must hv known that the explanation given by sir is not apt.
Ur physics is weak
@@thecurrentaffairs7962 the easiest thing in the world is to judge someone which requires little / no brains.
If you see the video properly, sir gave an analogy to understand the concept better. It has got more to do with the scope of audience. One has to go into the depths of Huygen's theory and Maxwell's equations to exactly understand the phenomenon of bending of light in refraction. I am very sure that sir could easily explain that, but again it goes back to the same question - "scope of audience". Sir is sharing videos for secondary and Sr secondary school. Sir used the analogy of car and rough road to explain how the phenomenon takes place.
And the comment I made is not just pertaining to this video, I have gone through the concepts of physics and it has influenced me a lot.
And coming to my physics knowledge, I don't mind someone calling me weak.... I only make sure that the slope of my learning curve is always positive.
@@jeswanthgrandhi that last line of yours was brilliant
HC sir explaining ANY DAMN THING makes me happy for some reason.
exactlyy
I think my teacher also watches Sir HCV ,because he answered the same as HCV sir answered this question. (But with mathematical proof)
He may also have the knowledge
@@shreyagupta1617 Yeah probably thats why he is the teacher and I am his student
@LeT's Play XII
Could u post the proof
Beta, teacher vale alag ho par science ek hi hai, toh ans to same hi hoga na
I always explained this to my students before they even asked and whenever I gave a similar example they would say "wow" ❤️. The best moment for a teacher !
From Snell's law: sini / sinr = n2/n1 = a constant, where n1and n2 are the refractive index of first and second medium respectively.
When light rays travel at some angle in one medium and goes into the other medium, the ratio of their refractive index remain constant so the ratio sini / sinr is also a constant. Hence, the angle of incidence 'i' and the angle of refraction 'r' would be different. That is why, light ray bends when goes from one media to other media.
This can also be explained on the basis of wave theory of light that may be a bit confusing for students below class XII.
Awesome Sir, what an analogy.!! Never thought of it like this.😊
Exactly
th-cam.com/video/NLmpNM0sgYk/w-d-xo.html check out this, its a wrong explanation by hc verma
It is wave front concept from hugyens wave theory in 2nd year
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
@@finisherx4108 Sir gave an analogy not an explanation... Question is asked by a class 10 students..he can't explain Maxwell equation to him at this level.
Sir this is the first time I have visited your channel and just within a minute of watching , your persona has started to impact me. Your books are undoubtedly amazing but today your personality and humble nature have also proved to be amazing and superrrr inspirational! Your videos have compelled me to change my perspective of looking at physics. Thank you so much sir , you're a gem!!!!!
For those who want to know more about it try to study huygen's principle . It was definitely wonderfully explained by Sir with an example . But you will get more feel or understanding if you specifically are looking for behavIour of light . Thanks
Practically physics is wow.
But jb ques solve kro to Physics jao 😂😂😂
Hehe same
Yes brother you are right practically its nothing but in terms of formulae and laws it is disgusting....😡😡😡
No bro, first u have to understand the question then you can answer, if u didn't understood then u may use the help of TH-cam.
Physics G@*d marao😂
Physics is seemingly very boring... But buried deep inside it are the mesmerizing wonders of our amazing reality!
Sir,I am A Student from Bankura zilla school,west Bengal. I am so happy to seeing this video.it's make my learning so easy.
Me also from W.B
I'm also form wb uttar dinajpur
Wb uttar dinajpur
Me from north 24 parganas
But how will it make your learning easy in a singl video?
This kind of explanation is also given in S. Chand book of physics for class 10, and they have also tried to explain in somewhat similar passion. But HC Verma Sir Explained it more properly, that's why he is the best.👍🏻
This example was used by a teacher in Khan Academy
Salute to you sir❤️🙏🏻
*Indian teacher : how dare you to ask such stupid questions that can't be asked in your so called prestigious board exam.*
*HC Verma : This new generation made for innovation and that's why this channel make themselves innovative.*
@krishna...pls don't use Indian teacher. Our country is famous for Guru culture.
" This que ll not be asked in exm" is told by many teachers who don't know the answer. This not only happens in india but in many countries their education system having problem like India presently having.( Reasons for this is many...mainly bcz of politicians) so.... please..
@YASH MALIK defending..!!??😃 Fr your kind info, I m a teacher.i never said this to my students till now. I even say u can ask out of syllabus, subject related silly questions also. I fixed it. Many are doing. I think u misunderstood my reply.
We are taught for marks not for education.
@@rajudai26 It's your perception . If you want to educate yourself you can do it and get more marks than what you study to get marks only .
@@akshaysekar355 Yeah you are right but I was saying some teachers are just teaching for marks. They want 1st rank in class but not everyone can be there. I want them to appreciate the child even when they score above 94% but they appreciate only to 1st rank holder. So sad.😞
If we understand refraction through Huygen's wave theory of light, then we can clearly understand why the light is bending in a optically denser medium....that car example is an easier version of that only....nicely explained...thank u sir...😀
yes brother by wave fronts we used to observe that thing.
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion.
Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html
I also request H C Verma sir to review and comment if any error.
th-cam.com/video/NLmpNM0sgYk/w-d-xo.html .What will be your observation after going through this video?
@@satyabachan8164 this one is correct version ...but the issue is if you are telling this to a normal board student it will fly over the head ...hence h.c . Verma sir version
@@Concefacts don't spam.
After getting this answer my mind just say this wow ! Just wow it was so overwhelming can't explain ...
Teachers have huge role in making physics more interesting....
भैया मुझे अभी तक समझ मे नही आया
प्लीज सिंपल में बता देंगे
बिहार बोर्ड के छात्र हैं
बहुत कृपा होगा आपका
Please
An extremely Incredible and knowledgeable teacher. Cleared my doubts regarding refraction.
Sir, you bring out the Beauty of Simplicity in Physics ❤️
th-cam.com/video/NLmpNM0sgYk/w-d-xo.html
This is the reason
ROSHAN physics thanks a lot!
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
When the Legend speaks, You listen! 👑
Just wow! It's amazing how he simplifies the concepts with analogies....
The answer is already in S Chand Physics for class 10th by Lakshmir Singh.
Very Good explaination by the great physicist.
I just never thought like this!
This is the reason why he is known as legend 🔥🔥🔥🔥
This is the best explanation ever!!! Thank you sir very much! I had this doubt for so long and no one was able to teach it to me! I dont know why I didn't look at it this way.
I am blessed to have stumbled upon this video and thankful to the person who asked this question!!!
I love how these videos go to the basic concept of the basics. Helps so much. Thank you sir for these amazing videos.
Here a Graduate Physicist.
I left here an additional very simple proof of this using the conservation of momentum of photons, for the ones who want to know more :)
If in medium 1 the index of refraction is n1 and in medium 2 the index of refraction is n2 and for the definition of index of refractions and wavelength we have:
n1 = c / v1 , v1 = λ1 * f
n2 = c / v2 , v2 = λ2 * f
Dividing the above equations we obtain: n2 / n1 = λ1 /λ2
So if n2 is higher than n1, the wavelength in medium 2 is smaller than in medium 1.
Now because the photon momentum is: p = h / λ
Applying the conservation of momentum of the incident and transmitted photon along the parallel line of medium separation:
p1 = p2 → h/λ1 *sin(θ1) = h/λ2 *sin(θ2) → n1 *sin(θ1) = n2 *sin(θ2)
This is the Snell Law!!
So the light bending is just a consequence of the conservation of momentum of photons!
i never understand these during board.....thnx for extra explanation
But how can you even apply conservation of momentum in parallel direction only but not in incident (normal to surface direction)....and why momentum of conserivation is applied when the photons expierence boundary resistance force upon entering the next medium i.e conservation law not valid...correct me if i am wrong
Finally sir is this theory approved and written in text books or your hypothesis only...?
@@cricobug9778 Very good question!
In the perpendicular direction the momentum is not conserved between the photons because the photons are exerting a perpendicular force in the material!
This phenomena is called radiation pressure and for example it's what makes solar sails to work.
Because no force is exerted in the parallel line of medium separation the photon momentum must be conserved along that direction.
This is analogous to a ball bouncing on the floor, the momentum of the ball is only conserved in the parallel line of the floor.
@@cricobug9778 This derivation is approved and very well documented. See for example: arxiv.org/pdf/physics/0502054.pdf
People who came to see how he teaches
He always teach best
@@kartikbhargava9873 teaches hoga
ME😂
Not everyone is like u
@@kartikbhargava9873 He always teaches very good / His teaching in the best
Nobody can explain it in way as H C verma sir explained. Sir you are a gem 💎
HC Verma Sir is different from the classical mold of teachers...he never disregards even a seemingly simple question such as this. I loved this analogy, its a new angle of thinking. Of course, it seemingly simplifies Huygens Principle to a greater extent.
I was curious to see his answer,so beautifully explained.
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Thank you so much, I had the same doubt but I couldn't understand what my teacher said. sir please keep answering our questions
H C Verma, a legend in the Indian school library and a savior in minds of students.
I just noticed that he has almost 3 lakh subs but he has not monetized even a single video..That is simply amazing..Respect!
I loved it .... Sir thanks for answering.... A lot of respect from me
Absolutely fabulous, never thought of why this phenomenon occurs
th-cam.com/video/NLmpNM0sgYk/w-d-xo.html
Dont be happy for no reason
See the real reason
@@thecurrentaffairs7962 being happy for no reason is the way to live what the hell are you talking about dude
@@thecurrentaffairs7962 read the room. This video was not directed towards physics graduates but to a school student. So don't try to act smarter than a legend😑
@@jakeperalta8421 school students study about dielectric medium and the decrease of electric field in dielectric medium.
It is not meant for kindergarten
@@jakeperalta8421 m not trying smarter than legend.
This is an analogy and not the reason why light bends
have never enjoyed the basic physics of life before. Thank you so much sir for starting this channel and been the Go To encyclopedia accessible for all the curious minds.
Your ability to make us understand concepts is amazing
He speaks like my grandfather who is also a physics teacher and a fantasizer of theoretical physics.
My teacher scolded my friend when he wants to know the answer of this
Hope Indian teaching system changes soon😒😒😒
I don't think it will. Cbse is focused on money an shit, they won't change.
@@harshildeora1001 ICSE is better
It is gonna change the circular is out... The whole education system is going to change
Nep:
We are taught for marks not for education.
Wow I never found a more beautiful analogy to understand scattering of light.
Dear Dr. Verma, thank you for this excellent and clear explanation!
Sir one day I will definately meet you. Once in my life it is my commitment I will definately complete it
May u clear jee and get iit kanpur cse branch
All the best
Yes surely you will
Can anyone tell me how can I ask any question like this from hc verma sir
Plz anyone tell me his e.mail adress
Plz
Good one 👌, I regret that i remained weak in physics, till medical College entry...
Sir, You're an inspiration to all of us. Your examples and approach to topics, it's all just simplified in a better manner! Concept of Physics has really helped me learn physics in a fun, more applicative and a beautiful conceptual interpretation. Thank you so much Sir!
Brilliant analogy. Jus amazing!!
I too question this in std 9.
I came to know the ans in class 12 after reading optics chapter.
But this man uses easiest way to explain that even a non science student can understand
Answer is not given in 12th. And answer is not in optics. Its in ELECTROSTATICS.
Plz get ur facts correct
I hv written then answer in one of the comments
th-cam.com/video/NLmpNM0sgYk/w-d-xo.html
I actually had the same doubt....
You clarified it perfectly....
Thankyou sir!!
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion.
Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html
I also request H C Verma sir to review and comment if any error.
This is the best explanation of this quiestion I have ever seen ...
Just loved it
Wow sir. Great explanation. Never thought of this. This explanation make me push more towards particle nature of light
Sir, I'm preparing for Jee mains and all I wanted to know before my preparation is how to get an idea on basics and fundamentals. And also I wanted to know that how to get full grip on physics
Sir, please explain the concepts of your book "concept of physics volume 1"
Interstingly, a question was asked in JEE Advanced 2023 on the exact same concept, and it was a very beautiful question indeed. It was that should light bend or not on normal incidence while refracting through a variable density glass slab and the very first thing clicked in my mind was, oh, maybe lets try using the Huygen's Wave Theory and draw some wavefronts, and it worked like a charm.
THANK YOU SIR FOR SUCH A SIMPLE AND EASY EXPLAINATION.
Sir then why light travelling in denser medium reflects back while it is entering into rarer medium
(incident angle is greater than critical angle)
There is a simple proof of this in the NCERT Book. In easy words it is because it bends so much thar it reflects. In the sense of the car as described in the video I can say that the car turns so much that it is equivalent to talking a U-turn hence it reflects back
Reflection is due to electron vibration
@@naveenmeena1832 light photons give their energy to electron of refracting material . These electrons transfer their energies in the forms of reflected and refracted rays.
Only few near surface electrons are able to produce reflecting rays hence reflection is just 4 to 5 percent
Physics is really interesting thing.
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
@@benYaakov yes you are right we need to explain it through the Maxwell's 2nd and 3rd equations. They prove it correctly. I think it is correct.👍👍👍👍👍
@@jabberhi5 yeah , you got it little
Didn't expected such a nice explanation! Thanks for the video
I am blessed that my teachers doesn't ignore such questions like others..
Sir i had a doubt that when a light ray incident normally on a interface of any two different mediam then is there any change in velocity before and after refraction ? Iam asking this because when the medium is changing no.of particals also change so there will be change in velocity
Yes the speed change. Becoz speed of light is E/B
The electric field vector of light decreases when it enters di electric medium such as glass or water
Number of particles has nothing to do with it. The dielectric constant matters
bhai mereko bhi smajhao iam in class 10th ye toh pta hai ki light bend hoti hai jo optically rarer to optically denser mai jaati hai pr ye wave theory kya hai
@@pranay1802 tum abhi nahi samajh paoge. Vectors samjho pehle.
Or mail me rosh 1414@gmail.com
Let me solve this = when coming light make right angle with denser medium. ( one more thing i want to add why we call a medium denser because it have more number of particles ) these particles are always moving . So when bunch of rays or i mean light comes with right angle one particle of denser medium first introduse with any one of ray. But other one rays are still moving with that speed. Because they are not still interact with any particle (distance between particle must) so and after fraction second second ray also interact with a particle of second medium now easliy you can see. When you jion both ends path of light band. Its solve. 😊 i fill happy if this help you buddy.
Good evening sir,
I have a small question too, why do most of the galaxies matter is in form of a spiral or a disc
Nature loves symmetry
mainly due to the attraction to the centre of the galaxy. a lot
of galaxies have a black hole as their core, and all the particles of the galaxy tend to follow a spiral-like trajectory which is basically orbital movement around an object of high mass
I have too questioned my teachers but they said " why ur asking a question like stupid" but now sir has explained me with a peace manner..😇
Very nicely explained sir with such an easy example! Sir has proven that only great teachers make concepts easy for their students! How many of u all agree with this?
Sir there is ques . That when reflection happens , there also refraction bcz it is entering from one medium to another but rather we say it is a reflection ..... Two medium for mirror are air and glass throw which it enters and reflected by the coating backside , so why here we say it is reflection but it can be refraction toooo ...
There is difference between mirror and glass.. mirror is coating on glass(opaque) and glass is transparent (mostly)
Dislike krne wale amir ghr k ldke h jinhe physics smjh ni aati
What an analogy! It's great!
I'm feeling proud that I already knew it but I still watched whole video just because HC Verma sir is teaching this 💗
sir H C verma
light photons can travel in a curve path (minimum time interval) under influence of strong gravity field or acceleration field
why light bends under medium ?
or simply slow its speed
it's hard to differentiate between two
speed of light reduces in water by constant factor but how water molecues reduce speed of photon ?? whereas size of photons are much smaller than molecules
is any correct models is available???
car model is not working ..
why nobody care about it
Light also bend in diffraction so what is different between both of them
Diffraction is bending around corners of an opaque obstacle and for observable bending dimension of obstacle(e.g. slit width or hole diameter etc) should be of d order of wavelength of light.
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion.
Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html
I also request H C Verma sir to review and comment if any error.
Medium is the same in diffraction
@@Concefacts don't spam
When i searched this question on TH-cam i didn't expect a clear answer but when i saw that sir has made a video about this my face immediately turned like this😃
cleared years old doubt of mine in just a few minutes while my teachers coudn't in years... feeling blessed to have a teacher like him.😇
Sir, Can universal gravitional constant 'G' help to understand or slove the total mass of universe ?
No buddy
It also requires other measures such as force masses n all
not possible
What is exact value of G
HC Verma: Shrikanth Mehto from Purolia
Captions: Rika Tomato from Korea😂
Thank you, this finally helped me understand refraction intuitively!
Finally I understand that topic . Thank you sir so much.
Great analogy of car to explain bending of light
You are my idol sir.....🙏🙏🙏🙏i am using your book and my all concept are becoming strong and strong day by day.....Thank you soooooo much sirrrrr guru 🙏🙏🙏
We are very blessed to be born in such a era of this digital world Generally the offline teachers don't behave in very good way when they hear such type of questions from us but now the Online teachers try their best to clarify the actual phenomenon working behind our so called notes which the early age of people used to rote in their times.
Thank You sir and all other teachers who have tried to clarify the tough concepts in very possible easy way
I had this question since class 8 but no one's answer was good enough forget about satisfying. So I forcefully stopped thinking about it until this day.Now I'm completely satisfied.Thanks to you sir.
To know the answer of this q.
We have to know THE FERMATS PRINCIPLE OF LEAST TIME.
*Light is a hurry.*
With the help of this we also able to prove Law of Reflection (i=r)
Yes..are you studying in 12 science?
I am in class 11 with PCM
Light always travels in the Least Time Path not in the Straight Line. I tried to Explain with quantum theory.
Also, I explained it practically, we have done one experiment by using household things like mirror, bowl and some water and made a prism by these things. Apart from this we tried to explain Ray Optics by quantum physics (quantum Law).In this video I have explained how light scatters after passing through a Prism and proved the thing by high school physics Snells Law which is a law of refraction and law of dispersion.
Must watch full video please: th-cam.com/video/yMSJXajIWXo/w-d-xo.html
I also request H C Verma sir to review and comment if any error.
bro are you come to know this fermats law of least time through Anand Srinivas sir (Byjus app) bcoz i also
Yes from class 10 byjus
How can I send my questions to sir hc verma.
Same here
You guys can email him . He answere them all but very rarely he make video on question
What is his email address
@@ELEGANTFOX what is the email address.
Beautifully explained, thank you very much! ❤️
Thankyou so much Sir. I also had doubt since my childhood days. I asked many teachers and also referred several books but I didn't get satisfactory answer which I have got now. Thankyou so so much Sir. You a true Gem of India
Sir in the title it should be "refraction" instead of "reflection".
Correct
The same analogy is applicable to reflection as well
The student asked as reflection.....he just named the video from student's question😁
Nobody:
Literally nobody:
TH-cam: RECOMMENDED 😅😅
The concept he used is called soldier analogy , and this analogy is incomplete and not perfect , ultimately I wanna say that his explanation is not 100% correct . I recommend you guys to watch the video of Fermilab TH-cam channel , he explains well , unlike these ordinary and incomplete explanations
Ohhh....superb, 'light is no a single ray' clears our 70% doubt..
Too good a question and a befitting simple answer.....as simple as it can be.
The Ans. Of this q. Can be find in the NCERT book of class 10th. The ans is written clearly on this book
Where?
Beta you are in 2020. Physics is not a joke any more. th-cam.com/video/NLmpNM0sgYk/w-d-xo.html
SIR WHERE ARE THE STUDENTS SENDING U DOUBTS?
IN TELEGRAM OR IN THE COMMENT SECTION...
As a mail
Excellent. This is why he is HC Verma
We are blessed to have a physics teacher like you sir
whenever i ask this question to my teacher then they says its a property of light but know i actually understand how it happen
Fermat's Principal of Least Time
I guess u got that from byjus
Lights in a hurry
YEa, that is for kids. Real reason comes from constant phase difference ( Hygens Principle, wavefronts )
Thank you sir for explaining with such great method.
My mind was blown. You are awesome sir
this is also explained in khan academy
Guys we are seeing this universe but if we go in quantum level then we saw that there is pure energy then why everything look like made up of particles?
physics has not come out of the egg. When it will break the shell ,then you will see everything in terms of energy and information. So till then just look at the egg.
One more thing..when physics will reach its childhood stage ,biology will be in its fertility state
U are India's pride sir. Thank you so much.
One word 'brilliant'!