$A$ boy travelling in an open car moving on a levelled road with constant speed tosses a ball vertically up in the air and catches it back. Sketch the motion of the ball as observed by a boy standing on the footpath. Give an explanation to support your diagram.

(N/A) The path of the ball as observed by a person standing on the footpath is parabolic.
When the ball is tossed,it possesses two components of velocity: a vertical component $(u_y)$ due to the toss and a horizontal component $(u_x)$ equal to the constant velocity of the car.
Since there is no horizontal acceleration acting on the ball,the horizontal velocity remains constant throughout the flight.
Simultaneously,the ball is under the influence of gravity,which causes a constant downward acceleration $(g)$.
The combination of uniform horizontal motion and uniformly accelerated vertical motion results in a parabolic trajectory for the ball relative to the stationary observer on the footpath.