Question: A particle is executing uniform circular motion with velocity $\vec{v}$ and acceleration $\vec{a}$. Which of the following is true?
A) $\vec{v}$ is a constant; $\vec{a}$ is not a constant
B) $\vec{v}$ is not a constant; $\vec{a}$ is not a constant
C) $\vec{v}$ is a constant; $\vec{a}$ is a constant
D) $\vec{v}$ is not a constant; $\vec{a}$ is a constant
Answer: $\vec{v}$ is not a constant; $\vec{a}$ is not a constant
Sol:
Direction of velocity and centripetal acceleration changes continuously so $\vec{v}$ is not constant and $\vec{a}$ is not a constant.
