What holds planets in their orbits around the Sun?

• mass

• inertia

• gravity

• gravity and inertia

How would a greater mass affect gravity between two objects?

• Gravity is not affected by mass

• Gravity would remain the same

• Gravity would increase

• Gravity would decrease

How is gravity affected by distance between two objects?

• Greater distance between two objects means greater gravity force

• Greater distance between two objects means less gravity force

• Gravity is not affected by distance

• Gravity is not affected by distance

Earth revolves around the sun, but it also makes one complete rotation. How long does it take Earth to make one complete rotation on its axis?

• 365 days

• 1 month

• 1 day

• 1 week

A year is the amount of time it takes a planet to make one ____________ around the Sun.

• Rotation

• Revolution

The spinning of the Earth on its axis is called

• rotation

• revolution

In this simple diagram, the motion of both the Earth and Moon moving around the Sun can be described as -

• Rotation
• Revolution

How long does it take for the Earth to make one full orbit around the Sun?

• one day
• one week
• one month
• one year

If Earth's rotation speeded up, what would happen?

• The year would get shorter

• The year would get longer

• The day would get longer

• The day would get shorter

What does a light-year measure?

• The speed of light

• The time it takes for Earth to orbit the Sun

• The time it takes light to travel in a year

• The distance that light can travel in a year