The angular speed of a wheel increases from $600 \, rpm$ to $1200 \, rpm$ in $10 \, s$. What is the angular acceleration?

If the length of the second's hand in a stop clock is $3 \, cm$,the angular velocity and linear velocity of the tip are:

$A$ particle moves along a circle of radius $\left( \frac{20}{\pi} \right) \, m$ with constant tangential acceleration. If the velocity of the particle is $80 \, m/s$ at the end of the second revolution after motion has begun,the tangential acceleration is

The angular acceleration of a body, moving along the circumference of a circle, is :

The ratio of the angular speed of a second-hand to the hour-hand of a watch is (in $: 1$)

The linear speed of the tip of the seconds hand of a wall clock is $1.05 \, cm \, s^{-1}$. The length of the seconds hand is nearly ........ $cm$.