Q6 of 43 Page 85

A stone is dropped from the window of a bus moving at 60 kmhr–1. If the window is 1.96 m high find the distance along the track which the stone moves before striking the ground.

Horizontal velocity = = 60 kmhr–1

Height of the window = H = 1.96 m


Horizontal range = ?


Now, we know that:


R = Horizontal Range = Distance along the track stone


makes before striking ground


So, where T = time of flight


Using equations of motion:




Now, for t = T


= g


= H (Vertical Distance)


= 0 (Initial vertical Speed)


So,




Now, = 60 kmhr–1 =


So,



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