A body, rpojected horizontally with a speed `u` from the top of a tower of height `h`, reaches the ground at a horizontally distance `R` from the tower. Another body, projected horizontally from the top of a tower of height `4h`, reaches the ground at horizontal distance `2R` from the tower. The initial speed of the second body is

Options

A. `u`
B. `2u`
C. `3u`
D. `4u`

Answer

A

Explanation

`y = (g x^(2))/(2 u^(2))`
`h = (g R^(2))/(2 u^(2)), 4h = (g(2 R)^(2))/(2 u_(1)^(2))`
`u_(1) = u`