The acceleration due to gravity on planet X is

one fifth that on the surface of the earth.
If it takes 3.5 s for an object to fall a certain
distance from rest on earth, how long would
it take to fall the same distance on planet X?
Answer in units of s.

1 answer

The time to fall a given distance is inversely proportional to the square root of g. That time is 2.24 times longer if the time is 5 times less.

What is 2.24 x 3.5 s ?