Calculating Inertia and Radius of Gyration for a Rolling Object

[shemy]

Right,

I need to find out the Radius of gyration of an object as it rolls down a ramp...

So I've got the equation

K=r square root((g.t^2 sin theta/ 2x) -1))

These are the numbers I have...

Object A

R = 0.004
g = 9.81
t = 16.45
theta = 5.31
x = 0.66


I got an answer of 0.054

I think that's right however to work out inertia you use the equation

Iz = MR^2 / 2

Should that give you inertia? I got an answer of 0.136

I don't if that answers still for K and I need to work out inertia still?

Cheers

Shemy

 

[shemy]

Anyone?