Question

if the displacement of body is zero, is it necessary that the distance covered by it is also zero

Answer 1

No, it is not necessary if the displacement of a body is zero, the distance covered by it is always zero.

Distance is scalar quantity but displacement is a vector quantity.

For illustration. If a person is walking on a circular track of radius (r ) and completes one revolution. Then its displacement is zero but the distance coverd=2πr.