Radius and centripetal relation

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 1K views
SUSUSUSUSUSUSUSU

Homework Statement


the file given

Homework Equations



F=mv^2/r

The Attempt at a Solution


I do not understand why the centripetal force is 2a and not 2/a since the radius of X is twice longer.

When I use the equation above, raidius is inversely proportional to the acceleration.

Is radius proportional to the accerlation? Then why it is?[/B]


 

Attachments

  • 스크린샷 2017-10-30 13.48.53.png
    스크린샷 2017-10-30 13.48.53.png
    17.2 KB · Views: 574
Physics news on Phys.org
Both speed and radius change. And I don't see how you would place the a in the denominator. That doesn't even give an acceleration in terms of units.
The angular velocity is constant. There is an expression for the acceleration that uses the angular velocity, that makes the problem easier.
 
so
mfb said:
Both speed and radius change. And I don't see how you would place the a in the denominator. That doesn't even give an acceleration in terms of units.
The angular velocity is constant. There is an expression for the acceleration that uses the angular velocity, that makes the problem easier.
sorry i got a/2 hahah
 
SUSUSUSUSUSUSUSU said:
so

sorry i got a/2 hahah

when i use 2R, the equation will be mv^2/2R which is a/2. this is what i have got