Science
What is Gravity?
Gravity is the force by which every object with mass attracts every other object. It's what gives things weight, keeps planets orbiting the Sun, and pulls a dropped apple back to the ground.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains gravity.
Key things to understand
- 1The more mass an object has, the stronger its gravitational pull; the farther apart two objects are, the weaker the pull.
- 2Newton described gravity as a force; Einstein's general relativity describes it as the curving of spacetime by mass.
- 3Earth's gravity accelerates falling objects at about 9.8 m/s², regardless of their mass (ignoring air resistance).
- 4Gravity has infinite range but gets weaker with the square of the distance (the inverse-square law).
Frequently asked questions
- Why don't we feel the Sun's gravity pulling us off Earth?
- We do feel it — it keeps Earth in orbit — but Earth's gravity is far stronger at the surface because we're so much closer to Earth's mass.
- Why do heavy and light objects fall at the same rate?
- Heavier objects feel more force but also resist acceleration more (more inertia). The two effects cancel, so all objects accelerate equally in a vacuum.
- Is there gravity in space?
- Yes. Astronauts float not because gravity is absent but because they're in continuous free fall around Earth — orbiting.