Newton's Laws of Motion: Laws + Forces

Newton’s First Law

An object at rest remains at rest and an object in motion continues in motion with a net force.

Newton’s Second Law

The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Newton’s Third Law

For every action force there is an equal and opposite force reaction. *requires two objects*

Friction

Contact force that resists the relative lateral motion or attempted motion of solid surfaces; parallel to the surface & opposite the direction of motion

Normal

Contact force exerted by a solid surface on an object resting upon or pressing against it; perpendicular to the surface

Spring

A restoring force exerted by a compressed or stretched spring; back into equilibrium position

Tension

Pulling force exerted by a string, rope, cable, or chain when attached to the body; parallel to the direction in which it is pulling

Weight

Force due to gravitational attraction between two bodies; straight down towards the Earth’s center

Applied

A force that is directly applied to an object by a person, animal, or any physical entity through a push or pull; acts in the direction of the physical push or pull