An object at an angle such that the horizontal range is 4 time of the maximum height. What is the angle of projection of the object?

Explanation

Given :
Horizontal range = 4 (maximum height)
Angle of projection `theta=?`
`R=4h_("maximum")`
Formula :
Range `R=(u^(2)sin2theta)/(g)`
`h_(maximum")=(u^(2)sin^(2)theta)/(2g)`
`R=4h_("maximum")`
`(u^(2)sin 2theta)/(g)=4xx(u^(2)sin^(2)theta)/(2g)`
`sin 2theta=2sin^(2)theta`
`2sin theta cos theta=2sin^(2)theta`
`therefore" "tan theta = 1 rArr theta=45^(@)`