CP - Gravitation Review

Because the Earth and Moon are gravitationally attracted towards each other, they will soon collide.

• True

• False

The gravitational force of the Earth on an object decreases as the object moves farther from the Earth.

• True

• False

If the Earth were its present volume but more massive, we would weigh more.

• True

• False

Newton hypothesized that the moon:

• is a projectile

• is actually attracted to the Earth

• Has tangential velocity that prevents it from falling into the Earth

• All of these

Newton reasoned that the gravitational attraction between the Earth and the Moon must be:

• directly proportional to the square of the distance between them.

• inversely proportional to the square of the distance between them

• the same at all distances.

• independent of distance.

Gravitational forces are the weakest forces found in nature.  Because of this:

• we can’t see the gravitational effect between a pencil and the earth

• there is no gravitational force between two 1kg masses.

• there is no movement between two 1kg masses located near each other in space

• gravitational effects easily observed involve one or more large masses

The gravitational force between two massive spheres

• is always an attraction

• depends on how massive they are

• depends inversely on the square of the distances between them

• all of these

If Fg between two balls is 10N.  If distance is cut 1/2 , what is the force between them?

• 40N

• 20N

• 5N

• 2.5N

If Fg between two balls is 10N.  If distance is doubled , what is the force between them?

• 40N

• 20N

• 5N

• 2.5N

The Sun actually pulls harder on the Earth’s oceans than the moon.

• True

• False