Physics - Picking up a rock requires less effort on the Moon than on Earth.

Picking up a rock requires less effort on the Moon than on Earth. 

a. How will the weaker gravitational force on the Moon’s surface affect the path of the rock if it is thrown horizontally?

Answer: Horizontal throwing requires the same effort because the inertial character, F ! ma, of the rock is involved. The mass of the rock depends only on the amount of matter in the rock, not on its location in the universe. The path would still be a parabola, but it could be much wider because the rock would go farther before it hits the ground, given the smaller acceleration rate and longer time of flight.

b. If the thrower accidentally drops the rock on her toe, will it hurt more or less than it would on Earth? Explain.

Answer: Assume the rocks would be dropped from the same height on Earth and on the Moon. It will hurt less because the smaller value of g on the Moon means that the rock strikes the toe with a smaller velocity than on Earth.