What is rigid body?

Similar Questions

Let $\mathop A\limits^ \to  $ be a unit vector along the axis of rotation of a purely rotating body and $\mathop B\limits^ \to  $ be a unit vector along the velocity of a particle $ P$ of the body away from the axis. The value of $\mathop A\limits^ \to  .\mathop B\limits^ \to  $ is

How can general body be obtained ?

Characteristic of rotational motion. 

How many degrees of freedom does a rotational motion about fixed axis ? 

Which forces needed for the rotational motion about a fixed axis ?