Gravity Effects
Elementary School
Definition
The results of gravity, the force that pulls objects with mass toward one another. Gravity keeps planets in orbit around the Sun, holds the Moon near Earth, and gives objects weight by pulling them toward the ground.
Worked examples
A ball dropped from a building accelerates downward at \(9.8 \, \)m/s\(^2\) due to Earth's gravity.
Gravity pulls the ball toward Earth's center, giving it weight and causing it to fall with acceleration.
The Moon orbits Earth in an ellipse because Earth's gravity continuously pulls it inward.
Without gravity's pull, the Moon would fly off in a straight line instead of staying in orbit.
A 5 kg textbook has a weight of \(49 \, \)N\(\) on Earth (\(5 \times 9.8\)).
Weight is the force of gravity acting on mass; the same book weighs less on the Moon where gravity is weaker.
Common mistakes
- Gravity only affects objects that are falling or moving. → Gravity constantly pulls on all objects with mass, even when they are stationary. A book resting on a table still experiences gravity pulling it down; the table pushes back to balance it.
- Weight and mass are the same thing. → Mass is the amount of matter; weight is the gravitational force on that mass. Your mass stays constant everywhere, but your weight changes on different planets because gravity differs.
- There is no gravity in space, which is why astronauts float. → Gravity exists in space; astronauts float because they are in free fall around Earth. The ISS and astronauts are constantly falling toward Earth but moving forward fast enough to keep missing it (orbit).
Where you'll use it next
You'll apply gravity effects when studying planetary motion and Kepler's laws, calculating orbital speeds, analyzing projectile motion in physics, and understanding tides caused by the Moon's gravitational pull on Earth's oceans.
See also
Reviewed by Pat Cheng, M.Ed. — StudyPug Curriculum Lead · Last updated June 6, 2026