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A particle performing uniform circular motion has angular frequency ω doubled & its kinetic energy halved, then the new angular momentum is

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

Correct answer: L/4

Solution

In uniform circular motion, angular momentum (L) is proportional to angular frequency (ω) and the moment of inertia (I). If the angular frequency is doubled (2ω) and the kinetic energy is halved, the relationship between kinetic energy and angular momentum shows that the new angular momentum is reduced to a quarter of the original, resulting in L/4.

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