Question

a stone is thrown from a bridge at an angle of 30° up with the horizontal with velocity of 25 m/s. If stone strikes the water after 2.5 seconds, calculate the height of the bridge from water surface.

Answer 1

S=ut+1/2at2

here, u = 30sin30degree (vertical) & a = g = -10m/s2

let the height be H,

So,substituting vaues of S,a and t in eqn 1 ..we get

-H=25sin30degree*2.5-1/2*10*2.52

=0