Ram dropped a cricket ball of mass 700 g from the top of a tower and the ball takes 5 s to reach the ground. He then determined the maximum velocity of the body by taking acceleration of the ball as `10 m s ^(-2)` find out the value of maximum velocity.

Explanation

Inittial velocity , u=0
Final velocity ,v = ` 72 km h^(-1) = 72 xx 5/18`
` 20 ms^(-1)`
Acceleration , a ` (v-u) /t= (20-0)/10 = 2 ms ^(-2)`