#2 #6 #10 #222. What force (if any) causes the planets to execute (nearly) circular orbits?
The gravitational force of attraction moves the planets in their nearly circular orbits.
6. Is the size of the gravitational force the earth exerts on the moon smaller than, larger than, or the same size as the force the moon exerts on the earth?
They are the same.
10. What happens to the volume of a cube if the length of each side is doubled? This is known as a cubic relationship.
The volume increases to eight times the original volume. Since the length of each side is doubled the volume, V = (2L)(2L)(2L) or 8 times the old volume.
22. An astronaut in the Space Shuttle feels "weightless." Is the gravitational force on the astronaut zero?
The gravitational force on the astronaut is not zero. In fact, the gravitational force is only slightly less than the astronaut's weight on the earth's surface.