What is a rigid body? Explain the concept of a rigid body.

(N/A) rigid body is defined as a system of particles in which the distance between any two particles remains constant,regardless of the external forces applied to it.
$1$. In a rigid body,the relative positions of all constituent particles do not change over time.
$2$. While a rigid body is an idealization (a theoretical concept),real-world objects like steel beams or wheels can be approximated as rigid bodies for many practical purposes.
$3$. Unlike a deformable solid,a rigid body cannot be compressed,stretched,or twisted.
$4$. Examples include a spinning wheel,a top,or a steel beam. In many mechanical problems,we ignore small deformations,vibrations,or bending to treat these objects as rigid bodies.