Gravity

Gravity

7th grade

Physical Science

Mr. Anglada

Multiple Choice

How many types of friction there are?

• 1

• 2

• 3

• 4

• 5

Multiple Choice

Throwing a book across the floor until it stops is an example of

• Sliding friction

• Rolling friction

• Fluid friction

• Static friction

Multiple Choice

The more rough a surface is, the ____ friction it will exert on moving objects.

• more

• less

Multiple Choice

How does friction affect speed?

• more friction decreases speed
• more friction increases speed
• less friction decreases speed

Multiple Choice

What direction does friction act relative to motion?

• in the same direction
• in the opposite direction 
• need more information
• depends on the force

Multiple Choice

What does friction produce?

• light
• sound
• heat
• gravity

Multiple Choice

 What is the unit called that measures force?

• weight
• meter
• Newton
• kilogram

Gravity

Gravity is a non-contact force.

It is defined as a force of attraction between two objects due to their masses.

Multiple Choice

Objects of any mass exert a gravitational force.

• True

• False

Gravity

Gravity is a result of mass. If an object has mass, it will be affected by gravity. You and I have mass.

This also means that every object is attracted to every other object.

Multiple Choice

Which of the following is true?

• I am pulling the Earth due to gravity

• The Earth is pulling me due to gravity

• Both Earth and I are pulling each other due to gravity

Why don't we notice this pull on Earth then?

Gravity's strength, as you will see, is dependent on mass. We, as humans, do not possess enough mass to have a noticeable effect on Earth's gravity.

Earth's gravity

Earth, however, is massive enough to have a noticeable effect on us and everything that surrounds us.

Multiple Choice

Is there gravity in the International Space Station?

• Yes

• No

Multiple Choice

Is there gravity in the middle of nowhere in space?

• Yes

• No

Multiple Choice

Which of the following do you think is true about satellites?

• Earth's gravity is significantly less

• Earth's gravity is greater

• Earth's gravity is about the same

• Earth's gravity is unpredictable