# Motion of ring/body down an incline

1. Oct 25, 2006

### konichiwa2x

A body of mass 'm' slides down an incline and reaches the bottom with a velocity 'v'. If the same mass were in the form of a ring which rolls down the incline, what would have been the velcity of the ring?

(A)$$v$$

(B)$$\sqrt{2}v$$

(C)$$\frac{1}{\sqrt{2}}v$$

(D)$$\frac{\sqrt{2}}{\sqrt{5}}v$$

Last edited: Oct 25, 2006
2. Oct 26, 2006

### OlderDan

Rolling implies rotational energy as well as translational energy. The knietic energy of the ring involves two terms, one for translation and one for rotation.

3. Oct 26, 2006

### konichiwa2x

ok

$$mgh = \frac{mv^2}{2} + \frac{I\omega^2}{2}$$

solving, $$velocity = \frac{v}{\sqrt{2}}$$