Question

A particle is acted upon by a constant force, the magnitude of which is always perpendicular to the velocity of the particle. The motion of the particle takes place in a plane. Which of the following can be true for the particle?

• A. Its velocity is changes.
• B. Its magnitude of acceleration is constant
• C. Its speed remains same and it is in circular motion
• D. (b) and (c) above.

Answer 1

The correct option is D (b) and (c) above.

As the direction of force is always perpendicular to the velocity, the particle is moving in a circular path.
Hence, the velocity of the particle will not be constant as its direction is changing continuously, but the speed will remain same.
If the particle is moving in a circular path, its magnitude of acceleration will be constant but direction will change.