The maximum range of a rifle bullet on the horizontal ground is `6 km`. Find its maximum range on an inclined of `30^@`.

Explanation

Maximum range on horizontal plane, `R = (u^2)/(g) = 6 km` (given)
Maximum range on a inclined plane, `R_(max) = (u^2)/(g(1 + sin prop))`
Putting `prop = 30^@`
`R_(max) = (u^2)/(g(1 + sin 30^@)) = (2)/(3) ((u^2)/(g)) = (2)/(3) xx 6 = 4 km`.