time taken by the object dropped = 2s
this time depends on the height of the plane from ground
it is given by

now the distance covered horizontally is given as 190 m
now the speed of the object is

now when plane is moving at same height but with double speed
so it will take same time to hit the ground again
so the time is given as

so it will take t = 2 s again to hit the ground
Mass = 0.5 kg
H = 20m
G = 9.8 m/s^2
U (Potential energy) = M×g×h
= 0.5 × 9.8 × 20 = 98 J
Yeah I have no clue what you saw me on lol yeah I
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Answer:
400k
Explanation:
Formula for KE = 
Plug in:
KE = 
KE =
× 2000 × 20^2
Solve:
1000 × 400 = 400,000 or 400k
Hope this helped.