Unit 4 Retest Quiz

Why do astronauts float when they are aboard the International Space Station?

• Because there is no gravity there

• Because the gravity from the Earth and the Sun balance out and the astronauts feel weightless

• Because the International Space Station is constantly falling towards Earth, so the astronauts are in free fall

• Because the scientists turn gravity off so that important experiments can be performed

Which pull is stronger - the Earth's gravity pulling on the moon, or the moon's gravity pulling on they Earth?

• The Earth's pull on the moon

• The moon's pull on the Earth

• We can't tell unless we know the masses of each object

• They are the same

When you jump into the air, which pull of gravity is stronger - the Earth pulling on you, or you pulling on the Earth?

• They are the same

• We need the mass of the Earth in order to calculate this

• The Earth pulls on you more

• You pull on the Earth more

When you jump off a tall surface, why do you move down towards the Earth instead of the Earth rising up to meet you?

• The Earth's pull on you is much greater than your pull on it

• You're already moving, so it's easier for you to go to the Earth than for it to come to you

• Both you and the Earth pull on each other equally, but you have less mass so your movement is greater

• The Earth is stuck in its orbit around the Sun and is unable to move

Which statement is true?

• Every single object (even the very small ones) have a gravitational pull

• Only objects with as much mass as a planet are able to create a gravitational pull

• Very small objects don't have gravity

• Only moving objects have gravity

You have your own gravitational field

• True

• False

What does Newton's Law of Universal Gravitation tell us?

• Large objects create gravitational field that influence smaller objects

• Gravitational force only exists between objects that are close together

• Gravitational force depends on mass, distance, and velocity

• Every object has a gravitational force that attracts every other object.

What is true about Newton's Law of Universal Gravitation?

• The mass of the objects and the distance between them are both directly proportional to the gravitational force.

• The mass of the objects and the distance between them are both inversely proportional to the gravitational force.

• The mass of the objects is inversely proportional and the distance of the objects is directly proportional to the gravitational force.

• The mass of the objects is directly proportional and the distance between the objects is inversely proportional to the gravitational force.

What will happen to the gravitational force between two objects when the mass of one of the objects is increased?

• The gravitational force will decrease

• The gravitational force will increase

• The gravitational force will stay the same

• We can't know for sure

What will happen to the gravitational force between two objects when the mass of one of the objects is decreased?

• The gravitational force will decrease

• The gravitational force will increase

• The gravitational force will stay the same

• We can't know for sure