A ballon moves up with a velocity `5 m//s`. A stone is thrown from it with a horizontal velocity `2 m//s` relative to it. The stone hits the ground at a point `10 m` horizontally away from it. (Take `g = 10 m//s^(2)`)

Options

A. the time of flight of the stone is `5` seconds
B. height of the ballon at the time of throwing the stone is `100 m`.
C. the speed with it will hit the ground is `40 m//s`
D. the time of flight of the stone will increase if the horizontal velocity of the stone is incresed.

Answer

A, B

Explanation

`10 = 2t`
`t = 5`
`H = ut + (1)/(2) at^(2) , = 5 xx 5 + (1)/(2)(-10)5^(2)`
`= 25 - 125 = 100`