Physics Laws & Theorems
Basic

Newton's First Law (Inertia)

An object stays at rest or in uniform motion unless acted on by a net force.

Formula

∑F=0⇒v=const\sum F = 0 \Rightarrow v = \text{const}

Variables

FNet force
vVelocity

Example

A puck on frictionless ice keeps gliding at constant speed until something pushes it.

Did You Know?

Inertia is why passengers lurch forward when a car brakes — their bodies want to keep moving.

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