Q3 of 43 Page 85

A body is projected with a velocity of 40 ms–1. After 2s it crosses a vertical pole of height 20.4m. Calculate the angle of projection and horizontal range.

Given: u = 40 ms–1

Ɵ = Angle of projection with horizontal




a = –g


t = 2 s


y = 20.4 m


Now, using equations of motion:








Now, Horizontal Range:





Hence angle of projection is 30° and the horizontal range is 141.39 m.


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