What is a rigid body? Explain the difference between a rigid body and a solid body.

(N/A) rigid body is defined as a system of particles in which the distance between any two particles remains invariant,regardless of the external forces applied.
$A$ rigid body has a definite shape and size that does not change under the action of external forces.
$A$ solid body is a state of matter that has a definite shape and volume,but it can be deformed (stretched,compressed,or bent) when external forces are applied.
The key difference is that a rigid body is an ideal concept where deformation is zero,whereas a solid body is a real-world object that exhibits some degree of elasticity or plasticity,meaning it can undergo deformation.
In practice,no real object is perfectly rigid; all solid bodies undergo some deformation under sufficiently large forces.