Question

a body having zero average velocity but not zero average speed justify in which giving example

Answer 1

because displacement can be zero as a body can return to its starting point and average velocity depends on displacement so it can be zero

while average speed depends on total path covered which cannot be zero even if it returns to its starting point so it cannot be zero

Answer 2

in circular motion
velocity =displacement/time
displacement after each circle its displacement is zero but its speed is not eqal to zero