Question

Chemical charateristics oxidation it is a very common pathway

Answer 1

after 2 seconds velocity is v
v = u+at
u=0 ,a=-g
v = -2g =-20m/s (downward)
distance covered in 2 second = S
v2 = u2+2aS
u=0 , a=-g
S = v2/2a = 400/20 =20
it has covered 20 m so remaining distance from ground is 200-20 = 180m
now gravity there is no gravity effect so a=0
now we use speed = distance/time
t = d/v
distance = 180 ,velocity = 20
t = 180/20 = 9sec
thus body will take further 9 sec to reach the ground...