Question

An astronaut that got stranded on a planet with unknown characteristics is at the top of a cliff. He does not know the acceleration of gravity on that planet, but owns a clock to make measurements. He wants to know the height of the mountain he's standing on, so he made two measurements.

First, he drops a rock from the border of the cliff and finds that it takes 2 seconds to touch the ground.

Then, he throws the another rock upwards from the same point, it goes up 1 meter and falls all the way down. This time it takes 2.34 seconds to touch the ground.

a) Find the value of gravity on the planet.

b) What is the height of the cliff/mountain?

Answer 1

gravity on planet is 20.12 m/s^2?
height of cliff is 20.24 m.

Thanks for asking.