Uniform Circular Motion Acceleration – Rankers Physics

Kinematics of Circular Motion: Practice Problem & Solution

Assertion (A): In uniform circular motion, angular acceleration is zero. Reason (R): In uniform circular motion, acceleration is 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

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Kinematics of Circular Motion. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true because angular speed \(omega\) is constant, thus \(alpha = domega/dt = 0\). Reason (R) is false; in uniform circular motion, the *magnitude* of acceleration is constant, but its *direction* continuously changes, so the acceleration vector is not constant.

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Similar Practice Questions

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1. Assertion (A): Infinitesimally small angular displacement is a vector quantity. Reason (R): Angular velocity doesn't depend upon reference frame.  
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