A ball of mass 1 kg is projected with `10ms^(-1)` froom the top of a toer of height 20 m. What is its speed when it is at vertical distance of 10 m below point of projection? `(g=10ms^(-2))`

Explanation

`DeltaK=K_(f)-K_(i)=1/2mv^(2)-1/2mu^(2)W_("gravity force")`
`baru=10m//s,v=?m=1kg,h=10m`
`DeltaK=K_(f)-K_(i)=W_("gravity force")`
`1/2xx1xxv^(2)-1/2xx1xx10^(2)=1xx10xx10`
`(v^(2))/(2)-50=100`
`v=sqrt300=17.32ms^(-1)`
`v=17.32ms^(-1)`