Question

for what angle of projection the kinetic energy at maximum height becomes 3/4th of its initial kinetic energy ?

Answer 1

If kinetic energy at maximum height is K’ and at initial point is K then both are related as
K’ = K Cos²θ ……[Here is the derivation of formula: https://brainly.in/question/1512907]
3K/4 = K Cos²θ
Cos²θ = 3/4
Square root on both sides
Cosθ = √3 / 2
Cosθ = Cos30
θ = 30°

Angle of projection should be 30°

Answer 2

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