Q22 of 37 Page 23

A boy throws a ball in air at 60° to the horizontal along a road with a speed of 10 m/s (36km/h). Another boy sitting in a passing by car observes the ball. Sketch the motion of the ball as observed by the boy in the car, if car has a speed of (18km/h). Give explanation to support your diagram.

Given:


Horizontal velocity of car


Vertical velocity of car


Velocity of car


Since the velocity of car is equal to the horizontal velocity of the ball, the ball only has vertical velocity with respect to the car.


Hence, the motion of the ball with respect to the car is a straight line.



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