JEE Main2016PhysicsRotational MotionActual
A cubical block of side 30 cm is moving with velocity 2 m s - 1 on a smooth horizontal surface. The surface has a bump at a point O as shown in the figure. The angular velocity (in rad/s) of the block immediately after it hits the bump, is :
Options
- A13.3
- B5.0
- C9.4
- D6.7
Correct answer
B. 5.0
Step-by-step solution
Conservation of angular momentum about point O , L before = L after ⇒ m v R = I ω ⇒ ω = m × 2 × a 2 m   a 2 6 + a 2 2 ⇒ ω = 12 8 a = 3 2 × 0 .3 = 10 2 = 5 rad   s - 1