During AMC testing, the AoPS Wiki is in read-only mode. No edits can be made.

# Difference between revisions of "Force"

A force, defined informally, is a "push or pull" on a physical body. The SI unit for force is the newton. Force has direction as well as magnitude, meaning it's a vector.

## Formal Definition

A force is that which may cause a physical body with mass to accelerate in a given direction. If the forces acting upon a body cancel out, then the body is in equilibrium and does not accelerate.

## Newton's Laws of Motion

Issac Newton, a brilliant scientist and mathematician, came up with three laws about motion, that somewhat relate to force: First Law: The first law, also known as the law of inertia, states that an object will remain at rest or at motion unless a force is applied to it. Second Law: $F=ma$ The second law states that force equals mass times acceleration. Third Law: For every force acting on an object, there is an equal and opposite force acting on it as well.