The relative angular speed of the hour hand and the second hand of a clock is (in $rad/s$):

If the frequency of an object in uniform circular motion is doubled,its acceleration becomes

$A$ particle performing $U.C.M.$ of radius $\frac{\pi}{2} \ m$ makes $x$ revolutions in time $t$. Its tangential velocity is

Is the tangential acceleration of a particle moving in a circular path always zero? Under what condition is it zero?

$A$ wheel,initially at rest,is rotated with a uniform angular acceleration. The wheel rotates through an angle ${\theta _1}$ in the first $1 \ s$ and through an additional angle ${\theta _2}$ in the next $1 \ s$. The ratio $\frac{{\theta _2}}{{\theta _1}}$ is

$A$ rotating wheel changes its angular speed from $ 1800 \ rpm $ to $ 3000 \ rpm $ in $ 20 \ s $. What is the angular acceleration,assuming it to be uniform?