# Recent questions tagged velocity-diagrams

A circular disk of radius $r$ is confined to roll without slipping at $P$ and $Q$ as shown in the figure. If the plates have velocities as shown, the magnitude of angular velocity of the disk is $\dfrac{V}{r} \\$ $\dfrac{V}{2r} \\$ $\dfrac{2V}{3r} \\$ $\dfrac{3V}{2r}$
A bullet spins as the shot is fired from a gun. For this purpose, two helical slots as shown in the figure are cut in the barrel. Projections $A$ and $B$ on the bullet engage in each of the slots. Helical slots are such that one turn of helix is completed over a distance of $0.5$ $m$. If velocity of bullet when it exits the barrel is $20$ $m/s$, its spinning speed in $rad/s$ is ________
A wheel of radius $r$ rolls without slipping on a horizontal surface shown below. If the velocity of point $P$ is $10$ $m/s$ in the horizontal direction, the magnitude of velocity of point $Q$ (in $m/s$) is ______