Rolling Without Slipping - A sticky adventure in rotation and translation | Doc Physics
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- Опубліковано 4 жов 2024
- How fast does the axle of a bike wheel move? How fast does the BOTTOM of a wheel move?
Editor's note - I found this 2012-vintage video on my hard drive. Never shared it, thought I'd been assigning it and teaching it for a while. Oops. Anyway, enjoy a timeless story of rotational dynamics.
It was very hard for me to accept that bottom of the body in rolling motion without slipping is at rest, but this video convinced me.... Thanks buddy.
I still find it hard to accept, care to explain it to me?
@@derryderry5672 Sure, you see velocity of the each particle in the rolling wheel is determined by the vector sum of the velocity of particle due to Rotation and Translatory motion. Since the velocity of the particle at the bottom end due to Rotation is tangential to the wheel towards left(in the case of moving wheel towards the right) and velocity due to Translatory is towards right. And they happen to be of same magnitude (which is only possible if wheel is moving without slipping) hence they cancel out. So the magnitude of velocity of bottom end is ZERO. But the top part is still moving, fastest of all the particles cause in top the velocity due to each case are in exact same direction, hence they add up.
@@derryderry5672 ua-cam.com/video/-4Fn6KWGCC0/v-deo.html
They see me rollin'... they slippin'
WhoWantsToKnow81 YESSSSSSSSSSSSSSSSSSS!
And trynna catch me rolling dirty.......
Trynna catch me rolling dirty
My rolling so fast they hate it...
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Got u nigga
you explained this SO well! my professor tried to dedicate time to discussing this which is great, but kind of sent us off with the notion that the top is 2vt without any explanation. this made so much sense, thank you!!
Just brushing up for a test, the enthusiasm got me excited, something I haven't had in a long time.
Thank You! That was a very nice explanation!
7:36 "Oh purple, purple"
Thank you sir for making this fun. No wonder there's a ring on that finger. 🤓
Good to see another video from you, even if it is 2012-vintage!
One of the terrible things of having studied physics is that you feel horror undertones in the simplest of explanations. Right now I hear a Vincent Price-like voice saying softly: Ball, ball, what about my ball, rolling without slipping? And then much louder: "Anholonomic!" followed by his typical spine chilling laugh.
Thank you. Very clear explanation. Paper, pen, ruler and a roll of tape. Simply work!
Wow.. that was some telpathy.. I was studying physics few mins back and wishing u had a vedio on this topic cause I reaally love em, and I just went to look for some other vids and then u uploaded!!! thanks a bunch!!!!!!!!!!!
i don't even take physics anymore but i still love watching your videos. thanks for posting!
That makes the two of us!
lope129 how?
Wow
Thank you very much sir, i am form India, and it is very difficult me to understand the rotational motional without slipping, but by your video i understand the whole concept, thank you sir.
Very clear talking about rolling without slipping
Excellent explanation....
you are the number 1 thank u so much!!!!!
Finally I got solution of problem that why contact point has zero velocity in rolling. Thank you very much.
ua-cam.com/video/-4Fn6KWGCC0/v-deo.html
Watching this after 9 years ❤❤
Very nice explanation.
your explanations are amazingggggggggggggg sir :D
ua-cam.com/video/-4Fn6KWGCC0/v-deo.html
You are my short period good sir!😌
By far the best explanation n video
great explanation of hard to accept fact! A kinematic way of looking at this problem is to note that the path taken by the particle on the edge of a wheel is a cycloid. now the parametric equations of a cycloid are x = r(t-sin t) , y = r(1-cos t) . by definition velocity of v = [(x')^2 + (y')^2]^0.5 , if you plug in t = 0,2pi,.. , n*2pi(the particle is at bottom when t=0,2pi,2*2pi,etc) , you get v = 0.
Awesome video sir..... thank you..... it's very easy to understand Physics when it happens practically infront our eye....
Great explanation. Thank you so much❤
thank you! and your voice is changing, that is really interesting
Good explanation ! Thanks !
excellent explanation.love u sir.☺finally i understood what is rotation motion
great job...exciting!
Thank you! I needed this!!
Thanks for the great explanation sir...
Helped in my assignment, thanks
thank you
Thanks a lot Sir....
Awesome😍 and thank you
thank you SIR.
best explanation on yt😍
AWESOME VIDEO BRO
this is good, wish I found this earlier
thank u so mush sir .such a nice video ...............
best explanation!
Good I'm impressed
Thank you!
Hi, Doc Schuster. I have a question about rolling with or without slipping in terms of friction. I did some problems and I realized when some object rolling without slipping, friction doesnt do work, but how about kinetic friction? Another problem is that if there's an external force acting on the object, but it is rolling without slipping, why does the work = external force times the distance travel. Shouldn't the friction force also do work to prevent the object from slipping? Thanks!!
Yes u are right the friction will do some work to prevent it from slipping and after sometimes it will attain a pure rolling motion ( rolling without slipping) but it will take some time .
friction doesn't do any work in rolling because bottom point is always at rest (W = FxD = 0)
for your 2nd question same answer
I'm trying to ferret whether any point on a rolling wheel can be said to be moving backward with respect to the track, if only for a fraction of the rotation.
if the object is performing linear motion than the center of mass is at the base
awesome
Still a very good explanation
I'm a little upset that I was guided to take college physics using simple formula style vs traditional calculus based style. Since I was not an engineering major it was recommended as being easiest for my science requirement. Problem is calculus style learning is better in understand core principals vs just calculating some convoluted simple problem.
Darth Nihiluz YES! How can we get this word out? Calculus makes things SIMPLER, not worse!
on the physics book, it says the Vcm = rw ,,,, HOW CRAZY IS THT....CANT UNDERSTAND
hi doc Schuster
if i'm not very advance in physics can you give me some help?
i really don't understand the concept of rolling can you explain more with some Q?
I can't understand when we say the point of contact has 0 velocity ,if it's having 0 velocity....why it's moving (why it's position is changing on the x-axis)?
When the mark is at bottom the mark IS ITSELF THE BOTTOM ....bbbUTT.. when the mark moves up...thr mark id no longer the bottom..then dome othet part of that wheel is the bottom...The bottom is the part touching the ground..dont confuse it with mark
superlike
the bottom being at rest for a rigid circular body seems like the biggest contradiction in history of physics lol
Please i need the video on how to solve this; A body of mass 20kg with reduce of 0.5m has both linear and angular velocity of 4m/s and 5rev/min, find its total kinetic energy
well thank you very much ...this really helped me 😋😋
Thx
So essentially slipping occurs when friction causes the velocity at the bottom to not be Vt?
Sorry, but i died when you draw the right side of a smiling circle at 03:35 hahaha..
and a Pac-Man
Once you see it, you can't unsee it......
Please can you make a video in which you explain the Cavendish experiment and how he calculated the universal gravitational attraction constant G ?
anoir trabelsi THAT is a great idea.
Did you sir make it already?
sir i cant picture how the point of contact is at rest.I mean you started from the zero mark and went on till some distance on the ruler.So the point has covered some distance in some time then how can it be at rest. :-(
instantaneously it is. as position is changing every moment
+anuj balodi Try looking at it as a simple motion equation (as he drawn it on the video). The velocity at the bottom of circle (or in real-world application, where the circle is in contact with the ground), is pointing toward the left for rotation, but pointing toward the right for translation.
one way to visualize how and why the Point of Contact has a Velocity of ZERO is to imagine a BULLDOZER... that's right... a BULLDOZER... you've seen a bulldozer with it's metal TRACKS. Notice how the Front and Back Wheels ride inside the Metal Track. Have you ever noticed how the Track that is on the Ground is NOT moving?.. but the Top Track is moving Foward?.. Now imagine the front and back wheels move toward each other and the track shortens. At some point the front and back wheel OVERLAP.. and the point on the bottom is at Zero Velocity.... good luck...
Philip Y thank u sir
This should be a top comment
Can anyone tell me in which grade are they learning this
Did you draw the whole concept of transational plus rotational =pure rolling?
Or is it from a book
How about a video on gyroscopic precession?
+Sherin Cherian A great idea! Thanks.
YOU SOUND LIKE NEIL PATRICK HARRIS AND I WISH YOU TAUGHT ME PHYSICS IN SCHOOL. GSGAFDGHFHAHÓ
i realized that too at 7:00
Question: is friction involved? is friction necessary?
yumasiancooking ..Unless you're really lucky, static friction at the bottom is needed to maintain rolling w/o slipping.
In the proof, you are actually assuming what u have to prove. You assumed that the tape took T time to complete one rotation (which in other words you have to prove)
Okay I love the video! Yet I get stuck I can't wrap my mind around the fact of how the top is 2Vt yet we are brought up in my physics class V=rw(romega) so when you ended the video with out clarifying on how the equation works with the 2Vt instead of just Vt i was left uneasy and confused. Can you break this down for me?
+sarah phillips That v from your class is the speed of the outside if the axle is still. Correspondingly, it will be the speed of the axle if the bottom is still, right?
+Doc Schuster okay I think I figured it out I talked about it with one of my fellow students in my class after presenting him with the video as well, he then said that the velocity would be relative to the ground looking in on the system from two different perspectives. therefore he first perspective being in the system yourself; for example sitting inside a rolling tire. the second perspective being a person observing you rolling in the tire and the tangential velocity would seem different to each observer. Can you further conclude on these statement telling whether or not I'm over thinking things?
+sarah phillips Sounds fine. in the tire, you think tangential v is r*omega. Outside, you see that v_t is zero at the bottom, r*omega on the sides, and 2*r*omega at the top.
+Doc Schuster so is that is why it's 2r*omega because in the specific example you are looking in on the system?
You have understand it.
Vaxle = Radius Omega = Tangenial Veolcity
Heey Doc could you make a video on gyroscopes mechanics
What about friction effects is it present or not
❤
You just gotta imagine it...no one can explain it to you...but still i will give a hint...think of the bottom's velocity at a particular instant....like if you take a picture of ussain bolt running and then look at the photo and say at THIS INSTANT his speed was v...take a picture of the wheel and analyse it..you will find that the bottom was at rest the upper part was moving 2v and the center was at v...and at each instant of whole process bottom was always at rest
Amana Prateek how bottom is at rest plz explain
Good job bro keep it up but you must watch the video of (PHYSICS WALA) who is the king of physics in India
is the friction of rolling maximum static friction ?
and why it is static friction why the velocity of contact surface is equal zero?
I really want to know why.
Great question! It need not be the maximum static friction. In fact, in equilibrium on a flat surface, objects continue to roll without slipping without any frictional force! As to your second question, you must get a bike tire and roll it around while thinking about it for a while to convince yourself.
Doc Schuster
that mean if the question give me the coefficient of static friction can i say friction=coefficient of static friction × normal force. with out find the acceleration of center of mass.
also if the surface is smooth is that make different or change the acceleration of center of mass
please answer me because I feel tired and my mind reproaches me
Hey DOC.. Great VIDEO!! as usual!! one way to visualize that the BOTTOM of a Tire has a velocity of ZERO.. is to Picture a BULLDOZER... that's right.. a BULLDOZER... you know how a BULLDOZER has those METAL TRACKS?... with a Wheel at the back and a wheel at the front?.. Yeah... Notice that when a Bulldozer is Moving along.. the BOTTOM of the metal track is AT REST!!!.. but the TOP track is moving at TWICE the velocity of the Bulldozer... that way it catches up... Can you Visualize that...????.. sure you can!... Thanks for the Inspiration... Yo, PEACE!! :)
Anyone from 🇮🇳India
Monty hall problem but make it physics
woooooo
how to equal V=Vt
Its not vt ...its v subscript t ... its v tangential ..like the velocity a ting along tangent ..seems like u have not studied circular motion
Hi
How bottom is at rest plz tell me
The contact point is at rest at that instant.
this is what you need ua-cam.com/video/-4Fn6KWGCC0/v-deo.html
Why am I watching this?
Brandon Cope HA! Good to hear from you.
Doc Schuster You too. College life is weird. lol
Goodbye
why the bottom is at rest? the mark is moving?
+Eat Shiit (tenacious pessimist) Try looking at it as a simple motion equation (as he drawn it on the video). The velocity at the bottom of circle (or in real-world application, where the circle is in contact with the ground), is pointing toward the left for rotation, but pointing toward the right for translation.
Assuming that both velocities are equal --> v(translation) - v(rotation) = 0. That is why the bottom of the circle is considered at rest.
Just remember that this is only true for pure rolling without slippage.
+Refuse to Eat Shiit (tenacious pessimist) The bottom of the body is "instantaneously" at rest. It doesn't mean that some point on the wheel is stuck to the platform all the time.
Rest doesn't meant Stuck at That Time.
excellent explanation.love u sir.☺finally i understood what is rotation motion