In uniform circular motion,the velocity vector and acceleration vector are

$A$ point $P$ is moving in uniform circular motion with radius $3 \ m$. Let at some instant the acceleration of the point be $a = (6 \hat{i} - 4 \hat{j}) \ m/s^2$, the position vector be $r$, and the velocity vector be $v$. Choose the correct statement.

Assertion $(A)$: The speed of a body in uniform circular motion is constant.
Reason $(R)$: In uniform circular motion,the acceleration of the body is constant.

Two particles $A$ and $B$ are moving in uniform circular motion in concentric circles of radii $r_{A}$ and $r_{B}$ with speeds $v_A$ and $v_B$ respectively. The time period of rotation is the same. The ratio of angular speed of $A$ to that of $B$ will be

The angular speed of the minute hand of a clock in degrees per second is

$A$ particle is performing $U.C.M.$ along the circumference of a circle of diameter $50 \ cm$ with a frequency of $2 \ Hz$. The acceleration of the particle in $m/s^2$ is: