Question

A ball dropped from a bridge strikes the water in 5 s.
Calculate
(a).the speed with which it strikes and
(b).the height of the bridge.

Answer 1

let g=10 m / sec²

t=5 sec

u=0 (as it is dropped from a rest position)

(a) v= u +at

       = 0 + 10 * 5

       = 50m/sec²

(b) s=ut+1/2gt²

      =0 +1/2*10*5*5

      =5*5*5

      = 125m