Question

a_r and a_t represent radial and tangential accelerations respectively. The motion of the particle is uniformly circular only if 

(A) a_r = 0 and a_t = 0

(B) a_r = 0 and a_t ≠ 0

(C) a_r ≠ 0 and a_t = 0

(D) a_r ≠ 0 and a_t ≠ 0 

Answer 1

The correct option- (C) a_r ≠ 0 and a_t = 0

Explanation:-

If a_r = 0, there is no radial acceleration and circular motion is not possible

So a_r ≠ 0

If at≠ 0 the motion is not uniform as angular velocity will change

So a_r ≠ 0 and at = 0 for uniform circular motion