Angular displacement - Rotational Motion Torque Angular Displacement Angular displacement is

To work out the linear velocity with respect to the center of the Earth, all you need to do is to multiply this result by of the latitude of your city.

The quoted established material is the fundamental answer to the question.

Rotation in the clockwise direction is negative and rotation in the counterclockwise direction is positive.

A body is generally considered rigid when the separations between all the particles remains constant throughout the body's motion, so for example parts of its mass are not flying off.