Answer –
(a) Consider a football, which is passed to player B by player A and then immediately kicked back to player A along the same path. The magnitude of the ball’s displacement is now 0 because it has returned to its original position. The overall length of the path travelled by the ball, however, is AB + BA = 2AB. As a result, the first quantity is clearly greater than the second.
( b ) Assume, in the foregoing example, that a football player covers the complete distance in t seconds. Then, the magnitude of the ball’s average velocity throughout time intervals. t = Displacement magnitude/time interval
t = 0 / = 0
The ball’s average speed during the same time interval is equal to the whole length of the path divided by the time interval.
= 2AB/t
As a result, the second quantity exceeds the first.
If the ball simply moves in one direction from one player to another, the above values are equivalent (considering one-dimensional motion).