Question

Let $a_r{a}_t$ represent radical and tangential accelerations. The motion of a particle may be circular if:(assume that only momentary rest is allowed)

• A. $a_r=a_t=0$
• B. $a_r=0and{a}_t\ne 0$
• C. $a_r\ne 0and{a}_t=0$
• D. $a_r\ne 0and{a}_t\ne 0$

Answer 1

The correct option is C $a_r\ne 0and{a}_t=0$

The tangential acceleration is the reason which makes a particle moving faster or slower in a circular motion. Since a uniform motion itself defines to be a constant velocity motion. Therefore tangential component of acceleration is zero.

If an object moving with constant speed in a circular path, the centripetal acceleration is constant. But due to constant change in direction, the radial acceleration is not constant.

Hence, $a_t=0and{a}_r\ne 0$