A particle performing uniform circular motion has angular momentum

• Rotational Motion

A particle performing uniform circular motion has angular momentum L. If its angular frequency is doubled and its kinetic energy halved, then the new angular momentum is

1. L/4
2. 4L
3. L/2
4. 2L

Answer

Angular Momentum, L = Iω

Rotational Kinetic Energy = ½Iω²

L/K = 2/ω

L = 2K/ω

Now, ω is doubled and K is halved.

L' = 2(½K)/(2ω) = K/2ω

L' = L/4

The correct option is A.