The acceleration of gravity at the surface of a newly discovered planet is 5.2 m/s^2. An astronaut throws a rock straight up at 10.5 m/s on this planet. How high will it go?

Please help!!!

1 answer

It will rise until it gains potential energy equal to the initial kinetic energy. That will happen at height H given by

M g H = (M/2) Vo^2
which can be rewritten

H = Vo^2/(2 g)

Use 5.2 m/s^2 for g, not the Earth's surface value of 9.8 m/s^2.

H = 10.6 m