Astronauts on the Apollo 17 mission to the moon in 1972 brought back samples of moon rocks to Earth. Which statement accurately describes the properties of the moon rocks on both the moon and on Earth?

Question

A.
The moon rocks had the same mass on the moon as they did on Earth, but they weighed more on Earth.
B.
The moon rocks had the same weight on the moon as they did on Earth, but they had a greater mass on Earth.
C.
The weight and mass of the moon rocks was greater on Earth than on the moon, and the rocks had no weight or mass during the trip when gravity was zero.
D.
The weight, but not the mass, of the moon rocks was greater on Earth than on the moon, and the rocks had no weight or mass during the trip when gravity was zero.

Answer 1

The correct statement is:

A. The moon rocks had the same mass on the moon as they did on Earth, but they weighed more on Earth.

Mass is a measure of the amount of matter in an object and remains constant regardless of location, so the moon rocks have the same mass on the Moon and on Earth. However, weight is the force of gravity acting on an object's mass, and since Earth's gravity is stronger than the Moon's gravity, the weight of the moon rocks is indeed greater on Earth than on the Moon.