Question

A body falls from a height of 120 m. After 2 s of

fall, if gravity disappears then total time taken to

reach the ground is (g = 10 m/s2​

Answer 1

distance travelled by body in intial 2s

s=ut^2+1/2*g*t^2

s=1/2(10*4)

s=20m

and velocity gained by body at 2s

v^2-u^2=2gs

v^2=2*10*20

v^2=400

v=20 m/s

after 2 s body will move with constant velocity

di stance travelled by body with constant velocity =120-20=100m

speed=distance/time

time=100/20=5s

total time taken by body when it reaches at ground = 5+2=7s

i hope it would help u