A stone is throw in a vertically upward direction with a velocity of `5ms^(-1)` if the stone during its motion is `10ms^(-2)` in the downward direction . What will be the height attained by the stone and how much time will it take to reach there ?

Explanation

`u=5" ms"^(-1)`
`a=-10" ms"^(-2)`
`v=0`
By third equation of motion,
`2as=v^(2)=u^(2)`
`rArr2xx(-10)xxs=(0)^(2)-(5)^(2)`
`rArr-20s=-25`
`rArr" "s=(25)/(20)=1.25m`
By first equation of motion,
`v=u+"at"`
`rArr t=(v-u)/(a)=((0-5)" ms"^(-1))/(-10" ms"^(-2))=1/2s`
`t=0.5` s