At what angle with the horizontal should a ball be thrown so that the range `R` is related to the time of flight as `R = 5 T^2` ? `(Take g = 10 ms^-2)`.

Options

A. `60^(@)`
B. `30^(@)`
C. `45^(@)`
D. `75^(@)`

Answer

a

Explanation

`R=5T^(2)`
`implies (u^(2)sin2 theta)/g=(5(u^(2)sin2 theta)^(2))/(g^(2))`
`implies 2u^(2) sin theta cos theta=(20(u^(2)sin^(2) theta))/g`
`implies tan theta=1 implies theta=45^(@)`