Question

Which of the following parameters of a particle executing uniform circular motion remains constant?

• A. Velocity
• B. Radial acceleration
• C. Angular velocity
• D. All of these

Answer 1

Answer: (C)

Angular velocity

Answer 2

The magnitude of the velocity of the particle, that is speed v remains constant and velocity vector changes from time to time. Therefore, it accelerates radially inwards. This is known as Centripetal acceleration, a_r. Its magnitude $\frac{v^{2}}{r}$ remains constant where as its direction changes from time to time. Therefore ${\overrightarrow{a}}_{r}$ is not constant. Since the sense of rotation of the particle remains constant its angular velocity $\overrightarrow{\omega}$remains constant in direction. Hence (3) is correct.