Question

On the Moon, where air resistance is negligible, an astronaut drops a rock from a cliff and notes that the rock has a speed v after falling from its point of release for a time t. Assuming that the rock does not hit the ground first, how fast will it be moving after it has fallen for a time 4t from its point of release?

Answer 1

4v

Step-by-step explanation:

If the rock has a speed v after falling from its point of release for a time t, we can calculate the gravitational acceleration on the moon:

`v = g_mt`

`g_m = v/t`

So after a time of 4t, its speed would be

`v_(4t) = g_m4t = (v)/(t)4t = 4v`