Why do we not apply force on all the particles of a door to open or close it?

The variation of angular position $\theta$ of a point on a rotating rigid body with time $t$ is shown in the figure. Is the body rotating clockwise or anti-clockwise?

Two masses $m$ and $2m$ are connected by a light string passing over a pulley (disc) of mass $M = 30m$ and radius $r = 0.1 \ m$. The pulley is mounted in a vertical plane and is free to rotate about its axis. The $2m$ mass is released from rest. Find its speed when it has descended through a height of $h = 3.6 \ m$. (Assume the string does not slip and $g = 10 \ m/s^2$)

Write the change in magnitude and direction of angular velocity with respect to time for a body rotating about a fixed axis.

As shown in the figure,a bob of mass $m$ is tied by a massless string whose other end portion is wound on a flywheel (disc) of radius $r$ and mass $m$. When released from rest,the bob starts falling vertically. When it has covered a distance of $h$,the angular speed of the wheel will be

$A$ rigid lamina is rotating about an axis passing perpendicular to its plane through point $O$ as shown in the figure. The angular velocity of point $B$ with respect to $A$ is ....... $rad/s$.