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Circular Motion concept

Toast210

Okay I really don't get this part of circular motion. How can there be no radial velocity yet a radial acceleration?

Reply 1

Joinedup

Original post by Toast210

Okay I really don't get this part of circular motion. How can there be no radial velocity yet a radial acceleration?

Well in circular motion the distance to the centre doesn't change... so no radial velocity.

if the mass wasn't accelerating it'd continue in a straight line forever... but it's got a force constantly pulling towards the centre of the circle... and a force acting on a mass gives an acceleration... because F=ma

Reply 2

Toast210

Thank you I think I'm starting to get it now. So an object doesn't have to move for it to accelerate, as long as there's a force acting on a mass?

Reply 3

Joinedup

Original post by Toast210

Thank you I think I'm starting to get it now. So an object doesn't have to move for it to accelerate, as long as there's a force acting on a mass?

Well it can accelerate radially without having radial velocity.

You could think about a body in circular motion as a body that would otherwise be going in a straight line but with every tiny bit of forward straight line motion, which would take it slightly further away from the centre, it also has a centripetal force accelerating it a bit towards the centre which eventually results in a complete circle.