Gravity and Motion

Gravity: Force that attracts all objects toward each other.

Force of gravity (between two objects) is affected by the masses of the objects and the distance between them.

Inertia: The tendency of an object to resist a change in motion.

An object with more mass has more inertia.

Objects with more inertia are harder to move and stop.

Newton's First Law: An object at rest will stay at rest, an object in motion will stay in motion unless acted on by a force.

Gravity and Inertia work to keep the moon in orbit around Earth.

Without gravity and inertia the moon would travel in a straight line.