Angular Momentum and Velocity of Center of Mass – Rankers Physics

Angular Momentum and Conservation of Angular Momentum: Practice Problem & Solution

Assertion (A): If there is no external torque on a body about its centre of mass, then the velocity of the center of mass remains constant. Reason (R): The angular momentum of a system always remains constant.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Angular Momentum and Conservation of Angular Momentum. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is false; constant COM velocity requires zero net external force, not zero external torque.

Reason (R) is false; angular momentum is conserved only when net external torque is zero.

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