Newton's First Law

An object at rest stays at rest, and an object in motion stays in motion at a constant velocity unless acted upon by an unbalanced force.

Inertia is the tendency of an object to resist changes in its state of motion.

Objects with greater mass have greater inertia, meaning they are harder to change their state of motion.

It remains at rest.

It continues to move at a constant velocity in a straight line.

An unbalanced force is a force that causes a change in the motion of an object.

The net force is the overall force acting on an object when all the individual forces are combined.

You add the magnitudes of the two forces.

A force is required to change the motion of an object.

It explains why seatbelts are important; they keep passengers in motion when a car suddenly stops.