An athlete runs along a circular track of diameter $80 \ m$. The distance travelled and the magnitude of displacement of the athlete when he covers $3/4$th of the circle is (in $m$):

$A$ particle is moving on a circular path with constant speed $v$. It moves between two points $A$ and $B$,which subtend an angle $60^{\circ}$ at the centre of the circle. The magnitude of the change in its velocity and the change in the magnitude of its velocity during motion from $A$ to $B$ are respectively ..........

$A$ scooter is going round a circular road of radius $100 \,m$ at a speed of $10 \,m/s$. The angular speed of the scooter will be ......... $rad/s$.

$A$ particle is performing uniform circular motion along the circumference of a circle of diameter $1 \ m$ with a frequency of $4 \ Hz$. The acceleration of the particle in $m/s^2$ is (in $\pi^2$)

$A$ particle revolves around a circular path. The acceleration of the particle is

$A$ particle moves in a circle of radius $25\, cm$ at two revolutions per second. The acceleration of the particle in $m/s^2$ is