# How does radial forc vary with the radius of its circular path?

1. Oct 16, 2009

1. The problem statement, all variables and given/known data

Its a conceptual question:

Theoretically, how does the radial force exerted on an object vary with the radius of its circular path when it is revolving: (a) at constant frequency? (b) with constant speed?

2. Relevant equations

F = mv^2/r

3. The attempt at a solution

Assuming that mass is constant, I had thought that the force would be inversely proportional to the radius of its circular path. I went to a physics tutor for help and now I am not sure of this lol - I am absolutely confused! :)

What I am really confused at it is what is the difference between speed and frequency? I know that frequency is cycles per second, but how are they different in this equation (F = mv^2/r)?

Thanks :)

2. Oct 16, 2009

### rl.bhat

F = m*v^2/r = m*ω^2*r = m*ω*v.
ω=2π*f and v can speed.

3. Oct 17, 2009

HI! :)

Thanks for asnwering! :) But I am still confused :)

I understand that Force is inversely proportional to Radius - but is it inversely proportional to radius when its at constant frequency? and constant speed?

I understand that ω=2π*f is equation for frequency.

hang on - does this mean that at constant frequency Force is directly proportional, but at constant speed force is inversely proportional??!! : )

4. Oct 17, 2009

### rl.bhat

Yes.

5. Oct 17, 2009

Thanks!! :)