Question

Which of the following statements is false for a particle moving in a circle with a constant angular speed?

• A. The velocity is tangent to the circle.
• B. The acceleration vector is tangent to the circle.
• C. The acceleration vector points to the centre of the circle.
• D. The velocity and acceleration vectors are perpendicular to each other.

Answer 1

The correct option is A The velocity is tangent to the circle.

For a particle moving in a circle with constant angular speed, the velocity vector is always tangent to the circle and the acceleration vector always points towards the centre of the circle or is always along the radius of the circle.
Since the tangential vector is perpendicular to radial vector, therefore, velocity vector will be perpendicular to the acceleration vector. Acceleration only causes change in direction of velocity at all instants of time because in no case, acceleration vector is tangent to the circle.

Hence option B is the only false statement.