Proffesor Dave, I watched your videos for calc 1 and 2, and gen chem and now, I watch them for physics, ochem, and multivariable calculus. Thank you so much. I couldn't do college without you, organic chemistry tutor, and Pauls online math notes
i love how he gives us real life examples of usage of torque instead of just telling us that it's a thing that exists that we simply have to accept immediately
Professor Dave- I just really want to say thanks - Your video's are helping me really understand and do well in my Engineering Physics class I love the way you explain Physics - YOU ROCK!!!!!!!!!
Because most people like watching stupid stuff, unfortunately. It's why we have 10 different housewives shows on tv, and why logan pual can be so famous, while having the brain capacity of a newt. It saddens me
My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s. If we say that the measure β of the angle is θ radians, we mean β = θ rad, and θ is the number of radians (it does not have the unit "rad"). For emphasis we can say that θ is measured in rad/rad = 1, since θ = β / (1 rad) and θ is a dimensionless variable.
When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent. What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
I had to skip this lesson to study for a calculus test I had the next day, and this video is extremely valuable to learn the topic, so good that I had to write a comment about it.
Many people wonder why radians do not appear when we have radians*meters. Here is an attempt at an explanation: Let s denote the length of an arc of a circle whose radius measures r. If the arc subtends an angle measuring β = n°, we can pose a rule of three: 360° _______ 2 • 𝜋 • r n° _______ s Then s = (n° / 360°) • 2 • 𝜋 • r If β = 180° (which means that n = 180, the number of degrees), then s = (180° / 360°) • 2 • 𝜋 • r The units "degrees" cancel out and the result is s = (1 / 2) • 2 • 𝜋 • r s = 𝜋 • r that is, half of the circumference 2 • 𝜋 • r. If the arc subtends an angle measuring β = θ rad, we can pose a rule of three: 2 • 𝜋 rad _______ 2 • 𝜋 • r θ rad _______ s Then s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r If β = 𝜋 rad (which means that θ = 𝜋, the number of radians), then s = (𝜋 rad / 2 • 𝜋 rad) • 2 • 𝜋 • r The units "radians" cancel out and the result is s = (1 / 2) • 2 • 𝜋 • r s = 𝜋 • r that is, half of the circumference 2 • 𝜋 • r. If we take the formula with the angles measured in radians, we can simplify s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r s = θ • r where θ denotes the "number of radians" (it does not have the unit "rad"). θ = β / (1 rad) and θ is a dimensionless variable [rad/rad = 1]. However, many consider θ to denote the measure of the angle and for the example believe that θ = 𝜋 rad and radians*meter results in meters rad • m = m since, according to them, the radian is a dimensionless unit. This solves the problem of units for them and, as it has served them for a long time, they see no need to change it. But the truth is that the solution is simpler, what they have to take into account is the meaning of the variables that appear in the formulas, i.e. θ is just the number of radians without the unit rad. Mathematics and Physics textbooks state that s = θ • r and then θ = s / r It seems that this formula led to the error of believing that 1 rad = 1 m/m = 1 and that the radian is a dimensionless derived unit as it appears in the International System of Units (SI), when in reality θ = 1 m/m = 1 and knowing θ = 1, the angle measures β = 1 rad. In the formula s = θ • r the variable θ is a dimensionless variable, it is a number without units, it is the number of radians. When confusing what θ represents in the formula, some mistakes are made in Physics in the units of certain quantities, such as angular speed. My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s = s^(-1).
PROFESSOR DAVE!! you are amazing ! these videos have literally changed my semester! spreading the word around class as best i can ! Also- you have to turn the jingle into a ringtone - the fam and i run around singing the song all day just for laughs
you are much better than my actual professor lol. I finally started understanding after this video. Thank you so much for sharing your knowledge to people :)
Hi @ProfessorDaveExplains I have a few questions about torque that I don't know if you already covered in this video, because to be honest, I didn't watch it all, but you are the only one on youtube making videos on this topic that replies. Here are my questions: 1. What absolutely decides whether rotation is clockwise and anti-clockwise? In a 3D spinning item, such as a bicycle wheel or even a ferris wheel like you said, has 2 sides. On one side, no matter how it spins, it will be clockwise, and the same wheel will appear to be anti-clockwise when viewed from the other side. 2. How does torque have a direction in or out of the page? I know the right hand rule RHR, but it doesn't explain anything. Taking the bicycle wheel or the ferris wheel as an example again, think about the axle: when looking at the wheel from the side so all you see is a thin rod, the axle sticks out on both the left and right, but when applying the RHR, and you pick a side, any side, your thumb will invariably end up pointing at either one of the left or the right... it's just a matter of which side you choose. Further, even if the sides don't matter for points 1 and 2 because the mathematical signs will reverse which ultimately end up cancelling, what does it mean when people say torque has a direction in or out of the page? If a spoke in the bicycle rotates as the wheel spins, it spins either clock or anti clockwise depending on how you look at it. The force applied to it is perpendicular to the spoke on the same 2D plane as that of the flat surface of the wheel. However, if you used the right hand rule, your thumb will point in either direction of the axle that sicks out. But that's not where the force is, you are not pushing on the wheel from the side (remember we are looking at the wheel from the side so we only see the thin profile of the wheel tread and no spokes). What is there? How can you say that "torque comes out or into the page/plane" when torque is the force you applied to it (eg to the spoke) to make it turn? Thank you in advance and sorry for the long question.
1. Nothing decides wether rotation is clockwise or anticlockwise,,, it is not an inherent thing of the universe (there’s not one right way), positive and negative is just the convention scientists chose. As you said, it depends on where you are looking from. So when doing exercises, the exercise will tell you where you are looking from. And in the example of the bicycle wheel, if we consider a bicycle in a 2D motion from left to right, using the right hand rule will give you the same result for torque’s direction wether you look from one side or the other (it is into the page) (remember to use the right hand, seems obvious but i’ve fucked up on that before🕊)
FYI: π is not pronounced as 'pie' in Greek, but more like a 'pe' instead. The same holds for the wave function in Quantum mechanics ie. 'pse' instead of 'psie'. Also, torque τ is read as 'taph' (or 'taf'') instead of 'tao' ('taou').
In English, we have to shift the vowel when we say the letter π. Otherwise it would sound identical to the Latin letter p. It is a consequence of the great vowel shift in the history of English. Other languages that use the Latin alphabet, call the letter "pay", instead of "pea", and can retain the original Greek name of π, and still tell them apart.
Hi - do I deduce correctly from your introduction (at 0:57) that uniform circular motion is translational motion? I quickly looked it up and one source says uniform circular motion is not translational motion, but rather a special form of rotational motion. I'm a bit confused with the new term "translational motion" in the context of your introduction. Can you please offer some explanation?
There are principles from both branches of classical mechanics, that apply to uniform circular motion. You can apply both the translational concepts to it, as well as the rotational concepts to it. The term translational motion, just means that it is based on moving the object in its current form from position A to position B, without rotating it, extending it, or flipping it. If an object were in pure translation during uniform circular motion, this would mean that one side of it constantly faces a fixed direction. So imagine painting a ball with half of it red, and the other half blue. Move it in a circular path, while a friend is watching you. Arrange it, so that the blue side always faces your stationary friend. This would be uniform circular motion in pure translation. This usually doesn't happen, because it is a lot easier to create uniform circular motion in a way that it coexists with rotation at the same rate, such that one side of it constantly faces the center. It is a lot easier for you to rotate the ball, so that the blue side constantly faces you, rather than so the blue side constantly faces your stationary friend.
Hey, would't the lever that will move the earth be faster than the speed of light since it will transfer force faster than light? So it will mean that something can travel faster than light?
in your example the rod was horizontally placed , what if the rod was vertically placed ? then the force ( torque) will be perpendicular to the rod and consequently sine turns into cosine ??
It's always sine theta because theta is the angle between the force (torque) and the plane of rotating object (in other words , the displacement vector )and not the angle between the force with the horizontal. Torque is force times the perpendicular distance between the force and plane of rotating object.
It's not insignificant. It is equal to 1 when the angle is 90 degrees, the largest value it can possibly equal. Due to this fact, multiplying by it has no impact on the equation.
Fulcrum means pivot point. It is the point where the lever is fixed in position, but free to rotate. As for how a planet can orbit without falling down, the planet has sufficient tangential speed. It is continuously falling and overshooting the "target" that is causing it to fall. The force of gravity causes change in direction, rather than change in speed. There is gravity everywhere in the universe, so if someone tells you "there is no gravity in space", they are either oversimplifying something, or giving you incorrect information. There is gravity in space. But that gravity is "used up" in causing an object to orbit, which causes objects inside an orbiting vehicle to not need any constraint force. It can seem like they are in a zero gravity environment. Consider what happens if you throw a ball perfectly horizontal. Initially, its velocity is horizontal. But gravity curves its path downward. Gravity is initially perpendicular to its velocity, where it can only cause a change in direction. Eventually, gravity starts to increase its speed, because it approaches the downward direction. What if you throw the ball so fast, that the Earth curves away from it, as fast as gravity can redirect its path? That is what orbit is. And if you neglect air drag, that speed would be 7.9 kilometers per second, and would circle the Earth in 84 minutes.
If you have two identical disks that you throw with the same linear speed, but give a spin to disk 1, and assume no air drag, they both will travel the same distance from the launch point to the first landing point.
@@ProfessorDaveExplains I support the Big Bang theory 100% I have a friend that asked me "How did the gas clouds whirl to form stellar objects to solve the the angular momentum problem. In other words, "In an isolated system the moment of inertia of a rotating object is doubled... if the system is an isolated one, no net torque acts on the object. Thus the angular momentum of the object must retain constant" Is there any truth in that? Btw I don't mind cash apping you a donation for your time. I couldn't find anyone who could spare the time. (2) then he asked how did gas push itself into solids.
@@ProfessorDaveExplains This was his last question "One third of the 55/60 moons rotate opposite to the rotational direction of their planets. How is that possible according to angular momentum"
Unbiased Sports Yes, angular momentum is constant. I talk all about star system formation in my astronomy tutorials, go check out that playlist for all the info you need. I also talk a bit about anomalous moons, the ones that spin the opposite direction of their planet are most likely captured objects from the Kuiper belt.
Dave is the guy who looks like he plays guitar in a grunge band until you realize he's the best physics/chemistry teacher online.
but i'm a grunge man at heart!
He always reminded me of Jesus
@@ProfessorDaveExplains I hope you will also release some of the grunge or guitar learning tutorials in soon
XD
@@alexanderkorol677 lol hahahahahaha
Once my physics course is over, I promise I will donate to your channel. Thank you, Professor.
Take my money too prof!!
👀
with certainty. just let me start earning. (I'm in 11th grade now🙂🙂)
🤒
@@cabbage5114 from India?
I like the way that you actually explain what torque is and not just how it is calculated
Thank you for another lucid, consumable video. Your work has genuinely gotten me through my semester. Please keep making more content!
Proffesor Dave, I watched your videos for calc 1 and 2, and gen chem and now, I watch them for physics, ochem, and multivariable calculus. Thank you so much. I couldn't do college without you, organic chemistry tutor, and Pauls online math notes
i love how he gives us real life examples of usage of torque instead of just telling us that it's a thing that exists that we simply have to accept immediately
I know right!!! He is so good
Professor Dave- I just really want to say thanks - Your video's are helping me really understand and do well in my Engineering Physics class
I love the way you explain Physics - YOU ROCK!!!!!!!!!
"Clocks are negative" is how my textbook said to remember that clockwise motion is negative and hence counterclockwise is positive.
This is seriously the best learning channel on TH-cam that is in English. Most other channels don’t go in as much depth as this one. 😄
his intros is one of the most underated , i can get it outta my head at all ever since i heard it .
Why doesn't this video have more views, why do you not have more subscribers, why do you not have thousands of likes?!?!?
i ask myself this every day! please tell your friends!
I know right, his videos are awesome. I’m doing well at physics bc of this videos.
@@jesushernandez-gw2qj - me as well he's AWESOME
Because most people like watching stupid stuff, unfortunately. It's why we have 10 different housewives shows on tv, and why logan pual can be so famous, while having the brain capacity of a newt. It saddens me
The pandemic is fixing that. I assign my students to watch a lot of Professor Dave vids, and I am not alone.
I didn't understand angular motion the whole semester and now, with a 7min video, everything makes sense ! Thank you so much, you're awesome :D
Professor dave saved my life.
Professor Dave is my baby Father
Same, man. Thank you, prof.!!!
facts
Guess who has their exam tomorrow?
You give the best explanation with nice pronunciation and accent you know🤩🤩
when professor dave helps you get a better understanding of physics than your actual physics teacher
My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s.
If we say that the measure β of the angle is θ radians, we mean β = θ rad, and θ is the number of radians (it does not have the unit "rad").
For emphasis we can say that θ is measured in rad/rad = 1, since θ = β / (1 rad) and θ is a dimensionless variable.
When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent.
What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
I had to skip this lesson to study for a calculus test I had the next day, and this video is extremely valuable to learn the topic, so good that I had to write a comment about it.
My favourite...i've been sharing it to my friends..keep up the good work sir
Many people wonder why radians do not appear when we have radians*meters.
Here is an attempt at an explanation:
Let s denote the length of an arc of a circle whose radius measures r.
If the arc subtends an angle measuring β = n°, we can pose a rule of three:
360° _______ 2 • 𝜋 • r
n° _______ s
Then
s = (n° / 360°) • 2 • 𝜋 • r
If β = 180° (which means that n = 180, the number of degrees), then
s = (180° / 360°) • 2 • 𝜋 • r
The units "degrees" cancel out and the result is
s = (1 / 2) • 2 • 𝜋 • r
s = 𝜋 • r
that is, half of the circumference 2 • 𝜋 • r.
If the arc subtends an angle measuring β = θ rad, we can pose a rule of three:
2 • 𝜋 rad _______ 2 • 𝜋 • r
θ rad _______ s
Then
s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
If β = 𝜋 rad (which means that θ = 𝜋, the number of radians), then
s = (𝜋 rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
The units "radians" cancel out and the result is
s = (1 / 2) • 2 • 𝜋 • r
s = 𝜋 • r
that is, half of the circumference 2 • 𝜋 • r.
If we take the formula with the angles measured in radians, we can simplify
s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
s = θ • r
where θ denotes the "number of radians" (it does not have the unit "rad").
θ = β / (1 rad)
and θ is a dimensionless variable [rad/rad = 1].
However, many consider θ to denote the measure of the angle and for the example believe that
θ = 𝜋 rad
and radians*meter results in meters
rad • m = m
since, according to them, the radian is a dimensionless unit. This solves the problem of units for them and, as it has served them for a long time, they see no need to change it. But the truth is that the solution is simpler, what they have to take into account is the meaning of the variables that appear in the formulas, i.e. θ is just the number of radians without the unit rad.
Mathematics and Physics textbooks state that
s = θ • r
and then
θ = s / r
It seems that this formula led to the error of believing that
1 rad = 1 m/m = 1
and that the radian is a dimensionless derived unit as it appears in the International System of Units (SI), when in reality
θ = 1 m/m = 1
and knowing θ = 1, the angle measures β = 1 rad.
In the formula
s = θ • r
the variable θ is a dimensionless variable, it is a number without units, it is the number of radians.
When confusing what θ represents in the formula, some mistakes are made in Physics in the units of certain quantities, such as angular speed.
My guess is that actually the angular speed ω is not measured in rad/s but in
(rad/rad)/s = 1/s = s^(-1).
You are a real professor. Your tutorial help me alot
watching this before my ap physics exam tomorrow. thanks sm for ur help this year.
Professor Dave is truly a science star.
dave single handedly saving my university career with his explanations
me and my friend like your introduction song very much
Even me and my fri -ends 😂
You are the reason I did so good on my OChem final. Hope it’ll help me pass physics!!
I like the way you discuss cause you give a background knowledge about the topic for us to easily catch up
SWEET AND SIMPLE
watching you from Pakistan
Professor your lectures help me a lot keep doing it i appreciate your work
professor dave has single-handedly explained the entire physics syllabus to me ill- let u know if i pass my exams -thanks professor!
This man is getting me through med school. Thanks bro.
hey sis, you graduated yet?
we promote professor dave in our room lmao
Thanks for the help I have an exam in a week and this video along with many others helped me to understand the concept.
I didn't know Dave also teaches physics and chemistry online besides his guitar playing in FooFighter
PROFESSOR DAVE!! you are amazing ! these videos have literally changed my semester! spreading the word around class as best i can ! Also- you have to turn the jingle into a ringtone - the fam and i run around singing the song all day just for laughs
I came into the right place, this channel is obviously a lifesaver
i love this channel so much
you are much better than my actual professor lol. I finally started understanding after this video. Thank you so much for sharing your knowledge to people :)
Oh, I loved this!
Great explanation. Thank you so much!
I wish I could have teacher like professor Dave in my school. He's really great.
When the video start I was sleepy, but as you arrive at Torque I stood up. KEA LEBOGA.
You really explain it well Sir....I was stuck in this concept like forever until I saw your vid thanks for the vid ❤️❤️❤️❤️...
there is a right hand rule for keeping track of positive or negative rotation that is much more robust and systematic than what he describes.
Ok so what does the 9.8 represent
Gravitational acceleration
Thank u professor Dave, I understand physics easily through your videos, keep it up sire :)
You're so clever and smart🤩
The best thing about prof. Dave is he quikly summarizes big stuff 🤯 in smaller chunks 👍🤩
Ap phys 1 cram be like
Dope Dave! Thank you!
sir Dave,nice video for understanding the conept
Hi @ProfessorDaveExplains I have a few questions about torque that I don't know if you already covered in this video, because to be honest, I didn't watch it all, but you are the only one on youtube making videos on this topic that replies.
Here are my questions:
1. What absolutely decides whether rotation is clockwise and anti-clockwise? In a 3D spinning item, such as a bicycle wheel or even a ferris wheel like you said, has 2 sides. On one side, no matter how it spins, it will be clockwise, and the same wheel will appear to be anti-clockwise when viewed from the other side.
2. How does torque have a direction in or out of the page? I know the right hand rule RHR, but it doesn't explain anything. Taking the bicycle wheel or the ferris wheel as an example again, think about the axle: when looking at the wheel from the side so all you see is a thin rod, the axle sticks out on both the left and right, but when applying the RHR, and you pick a side, any side, your thumb will invariably end up pointing at either one of the left or the right... it's just a matter of which side you choose.
Further, even if the sides don't matter for points 1 and 2 because the mathematical signs will reverse which ultimately end up cancelling, what does it mean when people say torque has a direction in or out of the page? If a spoke in the bicycle rotates as the wheel spins, it spins either clock or anti clockwise depending on how you look at it. The force applied to it is perpendicular to the spoke on the same 2D plane as that of the flat surface of the wheel. However, if you used the right hand rule, your thumb will point in either direction of the axle that sicks out. But that's not where the force is, you are not pushing on the wheel from the side (remember we are looking at the wheel from the side so we only see the thin profile of the wheel tread and no spokes). What is there? How can you say that "torque comes out or into the page/plane" when torque is the force you applied to it (eg to the spoke) to make it turn?
Thank you in advance and sorry for the long question.
1. Nothing decides wether rotation is clockwise or anticlockwise,,, it is not an inherent thing of the universe (there’s not one right way), positive and negative is just the convention scientists chose.
As you said, it depends on where you are looking from. So when doing exercises, the exercise will tell you where you are looking from.
And in the example of the bicycle wheel, if we consider a bicycle in a 2D motion from left to right, using the right hand rule will give you the same result for torque’s direction wether you look from one side or the other (it is into the page) (remember to use the right hand, seems obvious but i’ve fucked up on that before🕊)
wow, thanks a lot professor, this saved me a hour
Thanx Prof. Dave! 🎉
Loved this!
Thak you!! Great video!! I was really happy to find info about inbetween perpendicular applied force and parallel applied force for torque
maasyaalloh, what a helpful tutorial, always love your videos
You are amazing sir lots of love from india 🤞🤞💖
Amaaaaaazing brooo 😍😍😍😍😍😍🤍😍🤍😍🤍😍😍🤍
But what did Archimedes say next
He deserves everything 😭guys, please subscribe and like his videos.
So professor Dave is a proof of "not all heroes wear capes"
I love your work so much, but if you can extend your videos to go a bit slow while explaining, thanks for your patience
try setting it to 0.75 speed if you need more time
great video
good explaination
Dave is my super hero
Your birthday is in two days! Happy early birthday to our lord and savior!
thanks
Very good explanation Sir.., thank you
In jail, I could open the big metal doors with my hand right next to the hinge. Nobody else could.
3.3 mtr
sir the unit of torque is NM that is joules. so work, energy and torque are the same quantities?
FYI: π is not pronounced as 'pie' in Greek, but more like a 'pe' instead. The same holds for the wave function in Quantum mechanics ie. 'pse' instead of 'psie'. Also, torque τ is read as 'taph' (or 'taf'') instead of 'tao' ('taou').
im not interested in learning pronunciation
In English, we have to shift the vowel when we say the letter π. Otherwise it would sound identical to the Latin letter p. It is a consequence of the great vowel shift in the history of English. Other languages that use the Latin alphabet, call the letter "pay", instead of "pea", and can retain the original Greek name of π, and still tell them apart.
your awesome dave
After seeing this video I subscribed 👌👌 explanation
Thank you made me understand this,but sometimes are too fast when explain other topics like momentum
👍
Hi - do I deduce correctly from your introduction (at 0:57) that uniform circular motion is translational motion? I quickly looked it up and one source says uniform circular motion is not translational motion, but rather a special form of rotational motion. I'm a bit confused with the new term "translational motion" in the context of your introduction. Can you please offer some explanation?
There are principles from both branches of classical mechanics, that apply to uniform circular motion. You can apply both the translational concepts to it, as well as the rotational concepts to it.
The term translational motion, just means that it is based on moving the object in its current form from position A to position B, without rotating it, extending it, or flipping it.
If an object were in pure translation during uniform circular motion, this would mean that one side of it constantly faces a fixed direction. So imagine painting a ball with half of it red, and the other half blue. Move it in a circular path, while a friend is watching you. Arrange it, so that the blue side always faces your stationary friend. This would be uniform circular motion in pure translation.
This usually doesn't happen, because it is a lot easier to create uniform circular motion in a way that it coexists with rotation at the same rate, such that one side of it constantly faces the center. It is a lot easier for you to rotate the ball, so that the blue side constantly faces you, rather than so the blue side constantly faces your stationary friend.
Thank you so much
Hey, would't the lever that will move the earth be faster than the speed of light since it will transfer force faster than light? So it will mean that something can travel faster than light?
Now, I better understand my Beyblades :3.
Thankyou sir!
Thanks dude, this was great!
Thanks..you Mr❤
Sir, please make videos on moment of inertia
check out my tutorial on newton's first law of motion!
In the last question why net torque must be zero?
in your example the rod was horizontally placed , what if the rod was vertically placed ? then the force ( torque) will be perpendicular to the rod and consequently sine turns into cosine ??
It's always sine theta because theta is the angle between the force (torque) and the plane of rotating object (in other words , the displacement vector )and not the angle between the force with the horizontal. Torque is force times the perpendicular distance between the force and plane of rotating object.
Thanks a lot you're a savior 👍👍👍👍😁😁
That transition at the end tho lol :)
amazing video
Sir please also give us some more questions which are in HOTS so that we can know how to apply those concepts ! Thank you sir
He is the best.
Profesor Dave, do you have any videos on rolling without slipping motion?
Thank you sir
Nice one
Hey why didnt you incorporate the sin of the angle between the weight force and the seesaw in the end example, or is it insignificant
It's not insignificant. It is equal to 1 when the angle is 90 degrees, the largest value it can possibly equal. Due to this fact, multiplying by it has no impact on the equation.
What's meant by fulkrum nd
How can planet orbits rotating without falling down is there any gravity involvement,Make my doubt cleared
Fulcrum means pivot point. It is the point where the lever is fixed in position, but free to rotate.
As for how a planet can orbit without falling down, the planet has sufficient tangential speed. It is continuously falling and overshooting the "target" that is causing it to fall. The force of gravity causes change in direction, rather than change in speed. There is gravity everywhere in the universe, so if someone tells you "there is no gravity in space", they are either oversimplifying something, or giving you incorrect information. There is gravity in space. But that gravity is "used up" in causing an object to orbit, which causes objects inside an orbiting vehicle to not need any constraint force. It can seem like they are in a zero gravity environment.
Consider what happens if you throw a ball perfectly horizontal. Initially, its velocity is horizontal. But gravity curves its path downward. Gravity is initially perpendicular to its velocity, where it can only cause a change in direction. Eventually, gravity starts to increase its speed, because it approaches the downward direction. What if you throw the ball so fast, that the Earth curves away from it, as fast as gravity can redirect its path? That is what orbit is. And if you neglect air drag, that speed would be 7.9 kilometers per second, and would circle the Earth in 84 minutes.
So if you have a disk of the same mass and you spin them so that they fly through the air, will be spinning disc fly further? Or less?
If you have two identical disks that you throw with the same linear speed, but give a spin to disk 1, and assume no air drag, they both will travel the same distance from the launch point to the first landing point.
Dave is Scientific Jesus , common dude perform a miracle, water to wine but scientifically this time
You are the best!!!
So why do moons/stars spin backwards creating an angular problem?
I don't know what you're asking.
@@ProfessorDaveExplains I support the Big Bang theory 100% I have a friend that asked me "How did the gas clouds whirl to form stellar objects to solve the the angular momentum problem. In other words, "In an isolated system the moment of inertia of a rotating object is doubled... if the system is an isolated one, no net torque acts on the object. Thus the angular momentum of the object must retain constant" Is there any truth in that? Btw I don't mind cash apping you a donation for your time. I couldn't find anyone who could spare the time. (2) then he asked how did gas push itself into solids.
@@ProfessorDaveExplains This was his last question "One third of the 55/60 moons rotate opposite to the rotational direction of their planets. How is that possible according to angular momentum"
Unbiased Sports Yes, angular momentum is constant. I talk all about star system formation in my astronomy tutorials, go check out that playlist for all the info you need. I also talk a bit about anomalous moons, the ones that spin the opposite direction of their planet are most likely captured objects from the Kuiper belt.
@@ProfessorDaveExplains thank you. I will subscribe to your patreon
I like the "TAU" you pronounce😃🤪