Gravity Basics
Mass and Distance
Space and Gravity
Data and Evidence
Real-World Gravity
100
What is gravity?
A force that pulls objects toward each other.
100
How does mass affect gravitational force?
The greater the mass, the stronger the gravitational force.
100
What force keeps the planets in orbit around the Sun?
The suns gravitational force.
100
What happens to an object’s weight if gravity increases?
Its weight increases.
100
Why do we stay on the ground instead of floating into space?
Because Earth’s gravity pulls us downward.
200
Who discovered that all objects attract each other with a gravitational force?
Isaac Newton
200
How does distance affect gravitational force?
The greater the distance, the weaker the gravitational force.
200
Why does the Sun have the strongest gravitational pull in the solar system?
Because it has the greatest mass.
200
What evidence supports the idea that gravity depends on mass?
More massive planets have stronger gravity.
200
Why do satellites orbit Earth instead of falling down?
They move fast enough forward to stay in orbit while falling around Earth.
300
What direction does gravity always pull objects?
Toward the Center of the earth
300
If Earth were twice as massive, how would gravity on its surface change?
It would be stronger.
300
What two factors determine the strength of gravitational attraction between objects?
Mass and Distance
300
What evidence could you collect to support the claim that the Moon’s gravity is weaker than Earth’s? (Don't talk about the moon's mass)
Objects weight less on the moon than on the earth.
300
What causes ocean tides on Earth?
The gravitational pull of the Moon (and the Sun).
400
What keeps the Moon in orbit around Earth?
Earth's gravitational force
400
If two planets have the same mass but one is twice as far from the Sun, which has less gravitational pull from the Sun?
The one farther from the Sun.
400
Why do smaller planets like Mercury have less gravity than Earth?
They have less mass.
400
What kind of data would show that gravity decreases with distance?
Measuring weaker attraction between objects farther apart.
400
Why do objects fall at the same rate on Earth, regardless of their mass?
Air resistance aside, gravity accelerates all objects equally.
500
What tool do scientists use to measure the strength of gravity on Earth?
Spring Scale
500
What could be the reason Mercury and Venus don't have any moons?
The Sun's much larger gravitational pull 'steals' them.
500
What would happen to Earth if the Sun’s gravity suddenly disappeared?
Earth would move off a straight line into space.
500
How can you test how mass affects gravity using different-sized balls and a balance scale?
Compare their pull or weight — heavier balls show more gravitational pull.
500
Why would you weigh less on Mars than on Earth?
Mars has less mass, so it exerts a weaker gravitational pull.