Question

Calculate the angle of projection for which kinetic energy at the summit is equal to one fourth of its kinetic energy at point of projection
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Answer 1

Answer:

There is a much simpler solution to this.

The angle of projection is that whose tangent is the upward velocity divided by the horizontal velocity.

The energy goes like the square of the velocity.

So the square of the upward velocity is three times that of the vertical velocity.

So the angle is that with tangent root 3!

That angle is 60˚