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The angular momentum of a particle moving under a central force remains unchanged because the

1. torque acting on it is constant
2. force acting on it is constant
3. linear momentum of the particle is constant
4. torque acting on it is zero

Correct answer: torque acting on it is zero

Solution

The angular momentum of a particle remains constant when the net torque acting on it is zero, which occurs in a central force scenario where the force is directed towards a fixed point, resulting in no rotational influence.

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