Question

1. A stone is dropped from the roof of a building. It takes 2 s to reach the ground. What is the height of t building? [Use g=10ms] solve as fast as you can ​

Answer 1

Answer:

Correct option is

D

78.4m

The formula for time of flight is t=

g

2h

where h is the height from which ball is dropped.

since, t=4s

Putting the value in above formula,

4=

9.8

2h

Answer 2

u=0m/s

S=ut+1/2at^2

s= (0)(2)+1/2(10)(2)(2)

s=20m

Hope it helps