Question

a ball is projected vertically upwards with initial velocity of u goes to a maximum height h before coming to ground. what is value of h?

Answer 1

We know that a certain height is reached two times in a vertical projection.(One while going upward,one while going back downward) let the height reached in time t be hmaximum height=Hdifference in height=H-hnow H is reached in T and h is reached in t time.So H-h is reached in (T-t) time ...(1)while going back down H-h is reached in (T-t)secondsSo,H-h=u(T-t) + ½g(T-t)2but u =0 (velocity at max height is zero)So,H-h = ½g(T-t)2h = H – ½g(T-t)2  or  H – ½g(t-T)2