Question

A stone is allowed to fall the top of a tower of hundred metre high and at the same time another stone is projected vertically upward from the ground with a velocity of 25 metre per second calculate when and where they will meet each other

Answer 1

at the middle due to kinetic energy and acceleration through gravity

Answer 2

Given,

Let the heights be h1 and h2

V1 = 0 m/s

V2 = 25 m/s

Acceleration = 10 m/s²

Now,

S = ut+1/2*at²

S = ½*10*t²

S = 5t²

Again,

S = ut+1/2at²

S = 25*t+1/2-10*t²

S = 25t-5t²

Now,

H1+H2 = 100

Therefore,

-5t² + 25t-5t² = 100

25t = 100

T = 4 sec

Therefore time = 4 sec and

H1 = 5t² = 5*16 = 80 m

And H2 = 25t-5t² = 25*4-5*16 = 100-80 = 20m

 

I hope it helps……