Question

Two balls are projected simultaneously with the same speed from the top of a tower, one vertically upwards and the other vertically downwards. They reach the ground in 9 s and 4 s, respectively. The height of the tower is `(g=10 m//s^(2))`
A. 90 m
B. 180 m
C. 270 m
D. 360 m

Answer 1

Correct Answer - B

Ball 1: -`h=uxx9-1/2g(9)^(2) …(i)`
Ball 2: `h=uxx4+1/2gxx(4)^(2)`
Solving, `h=180 m`