A boy completes one round of a circular track of diameter 200 m in 30 s. What will be the displacement at the end of 3 minutes and 45 seconds ?

Displacement is a vector quantity defined as the shortest straight-line distance between the initial and final positions. In circular motion, after completing one or more full rounds, the displacement is zero because the final position is the same as the initial position. After half a round, the final position is diametrically opposite the initial position.