A stone is dropped from a height h. Simultaneously, another stone is thrown up from the ground which reaches a height 4 h. The two stones cross each other after time xhyg . Find x+y.

For first stone u=0 andFor second stone u22g=4h⇒u2=8gh∴u=8gh Total distance to be covered is ‘h’ where the initial velocity of stones are where, t = time to cross each other.∵h1+h2=h12gt2+8ght−12gt2=h⇒t=h8gh=h8g