A ball of mass $0.1$ kg is suspended by a string. It is displaced through an angle of ${60^o}$ and left. When the ball passes through the mean position, the tension in the string is ........ $N$

A grinding wheel attained a velocity of $20\,rad/sec$ in $5\,sec$ starting from rest. Find the number of revolution made by the wheel

A car changes speed from $18\,km/h$ to $36\,km/h$ in $5\,s$. The diameter of its wheel is $0.8\,m$ . The angular acceleration of the wheel is ........ $rad/s^2$

What is uniform circular motion ? By using proper figure, obtain equation of acceleration ${a_c}\, = \,\frac{{{v^2}}}{r}$ for uniform circular motion. Show that its direction is towards centre.

A smooth wire of length $2\pi r$ is bent into a circle and kept in a vertical plane. A bead can slide smoothly on the wire. When the circle is rotating with angular speed $\omega$ about the vertical diameter $AB$, as shown in figure, the bead is at rest with respect to the circular ring at position $P$ as shown. Then the value of $\omega^2$ is equal to

A car is moving in a circular horizontal track of radius $10\, m$ with a constant speed of $10 \,m/sec$. A plumb bob is suspended from the roof of the car by a light rigid rod of length $1.00\, m$. The angle made by the rod with track is ........ $^o$