Gravity
The attractive force between objects; the force that moves objects downhill.
Force
A push or pull exerted on an object.
Law of gravitational pull
The scientific law that states that every object in the universe attracts every other object.
Mass
The amount of matter in an object.
Weight
A measure of the force of gravity on an object.
Inertia
The tendency of an object to resist a change in motion.
Newton’s first law of motion
The scientific law that states that an object at rest will stay at rest and an object in motion will stay in motion with a constant speed and direction unless acted on by a force.