- #1
Euclid
- 214
- 0
A uniform cube is positioned in unstable equilibrium on one of its edges. It's given a small nudge. Show the angular velocity when one face hits the ground is [tex] \frac{12g}{5l}(\sqrt{2}-1)[/tex], when the block slips without friction, where l is the length of its side.
It seems to me the best approach is to use energy conservation:
[tex]mg\frac{l}{\sqrt{2}}=\frac{1}{2}I_{CM}\omega^2+\frac{1}{2}mv_{CM}^2+mg\frac{l}{2}[/tex]. However, the difficulty seems to arise in finding a relation between v_CM and \omega. Any ideas?
It seems to me the best approach is to use energy conservation:
[tex]mg\frac{l}{\sqrt{2}}=\frac{1}{2}I_{CM}\omega^2+\frac{1}{2}mv_{CM}^2+mg\frac{l}{2}[/tex]. However, the difficulty seems to arise in finding a relation between v_CM and \omega. Any ideas?