Competency #1
Answer and Explanation
Air Resistance
On the surface of the earth, air resistance will act on objects in motion. However, since the moon has no atmosphere, there will be no air resistance on the surface of the moon.
Gravity
On the surface of the earth, there is gravity between the earth and the object. However, on the surface of the moon, the most significant gravitational force is between the moon and the object. For an object on the moon, there will still be a gravitational force between that object and the earth, but this force will be extremely small due to the large distance between the object and the earth. The force of gravity of an object on the surface of the earth will be greater than the force of gravity of that same object on the surface of the moon, due to the earth's larger mass.
Consider a 100-kg astronaut. On the surface of the earth, there will be a force of gravity of 980 N between the astronaut and the earth. On the surface of the moon, there will be a force of gravity of 162 N between the astronaut and the moon. While on the surface of the moon, there will be a force of gravity of 0.3 N between the astronaut and the earth.
For an astronaut on the surface of the earth:
For an astronaut on the surface of the moon:
