The direction of angular acceleration of a body moving in a circle in the plane of the paper is

$A$ body is revolving with a uniform speed $v$ in a circle of radius $r$. The tangential acceleration is

An object moves along a circle with normal acceleration proportional to $t^\alpha$, where $t$ is the time and $\alpha$ is a positive constant. The power developed by all the forces acting on the object will have time dependence proportional to

How many revolutions must a wheel complete to attain an angular velocity of $20 \, rad/s$ in $5 \, s$ starting from rest?

$A$ disc,initially at rest,is rotated about its axis with a uniform angular acceleration. In the first $2 \ s$,it rotates through an angle $\theta$. In the next $2 \ s$,the disc will rotate through an angle:

$A$ particle moves along a circle of radius $r$ with constant tangential acceleration. If the velocity of the particle is $v$ at the end of the second revolution after the motion has started,then the tangential acceleration is