A hiker stands on the edge of horizontally with an initial speed if `15 ms^(-1)` . Negkectubg aur resustabce, find the time taken by the stone to reach the ground, and the speed with which it hits the ground. Take `g= 9.8 m//s^(2)`.

Explanation

Here, `h =490 m, u_(x) =15 ms^(-1)`,
a_(y) =9.8 ms^(-1) , a_(x) =0`
`t= sqrt (2 h)/g = sqrt (( 2xx 4 90) /(9.8) = 10 s`
` v_(x) =u_(x) + a_(x) t=15 + 0 xx 10 =15 m//s`
` v_(y) =u_(y) + a_(y) t= 0 + 9.8 xx 10 =98 m//s`
:. ` v= sqrt (v_(x)^(2) + v_(y)^(2)) =sqrt( 15^(2) + 98^(2)) = 99.1 m//s`.