could anyone pls explain to me why the tangential velocity of every point on the rim of a rotating body (without slipping) is different?

Question

anonymous · Answer

I don't understand the question

anonymous · Answer

the question (in 2D) is this..
The element x located at the rim of a circular body rotating (without slipping) on a horizontal surface.
Explain the change in tangential (or linear) velocity of the element when it is
1) at the top of the body
2) at the line passing through the centre of the body parallel to the surface
3) at the bottom of the body..

fifciol · Answer

the velocity is a vector. In uniform circular motion velocity changes all the time but speed(scalar, the magnitude of velocity) does not change. so the velocity vector can be changed not only by changing its magnitude but also by changing its direction(

anonymous · Answer

yea.. but you said without slipping.. so that means are you talking about ROLLING? cause in rolling.. even the SPEEDs are different

isaiah.feynman · Answer

An alternative answer would be to read uniform circular motion in your text book. Its half a page long.

anonymous · Answer

lol, well none of that did come to my use..
what did seem to come to my help was a dream...
as the body rolls without slipping, friction acts at the most bottom point of the rolling body..
so, we can assume the horizontal surface to be the axis of the body's rotation..
in this case, the bottom point is actually rolling on the axis..
w (omega) is the motion speed of the body per metre.. [which is unity for uniform circular motion]
hence at the topmost point, velocity = rw 
while at the bottommost point, velocity = 0 [r = 0]
and at the mid point, velocity = rw/2 [which is the motions of the body..]

vincent-lyon.fr · Answer

Actually, not only points on the rim, but ALL points of a rotating body have different velocities.