A metal ball of mass 5 kg falls from a height of 490 m. How much time will it take to reach the ground ?

Explanation

GIven : `s=490m, a=g = 9.8m//s^(2)`,
`u=0m//s, s=ut+(1)/(2)at^(2)`
`therefore 490=0xxt+(1)/(2)xx9.8xxt^(2)=4.9t^(2)`
`therefore t^(2)=(490)/(4.9)=100`
`therefore t=10s`.