Question

A stone dropped frm a top of tower is found to travel 5/9 of the height of tower during last second of its fall. the time offall is

Answer 1

For complete journey
H = 0.5gT^2

For first 4H/9 journey
4H/9 = 0.5g(T - 1)^2

Divide above two equations

9/4 = [T / (T - 1)]^2
3/2 = T / (T - 1)
2T = 3T - 3
T = 3 seconds

Time of fall is 3 seconds