Answer to Question #15518 in Mechanics | Relativity for Rhyse Vivens

Question

Acceleration due to gravity on planet X is 1/5 that on the surface of the earth. If it takes 4 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

Answer 1

Let's find the height that an object falls from on earth by 4 seconds:

H = gt²/2 = 9.8[m/s²]*(4[s])²/2 = 78.4 metres.

So, the time needed to fall 78.4 metres on the planet X is

T = √(2*78.4[m]/(9.8/5[m/s²])) ≈ 17.53 seconds.