Q14 of 31 Page 143

A stone is released from the top of a tower of height 19.6 m. Calculate its final velocity just before touching the ground.

Given,

Initial velocity, u = 0


Final velocity, v =?


Acceleration due to gravity, g = 9.8 m/s2


Height, h = 19.6 m


We know that,


v2 = u2 + 2gh


= (0)2 + 2 × 9.8 × 19.6


= 19.6 × 19.6


= (19.6)2


= 19.6 m/s


Therefore, its final velocity just before touching the ground is 19.6 m/s.


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