Chapter 2: Newton's First Law

Natural Motion

motion that is straight up or straight down

Violent Motion

imposed motion resulting from an external push or pull

Force

A push or a pull

Inertia

The tendency of an object to resist a change in motion

Mass

the amount of matter in an object

Objects at rest...

stay at rest

Objects in motion...

stay in motion

vector

A quantity that has magnitude and direction

contact forces

forces that have an effect only on objects that they touch

long range forces

forces that act on an object without physical contact

net force

The combination of all forces acting on an object

The equilibrium rule

The vector sum of forces acting on a nonaccelerating object equals 0

speed

The distance an object travels per unit of time

velocity

Speed in a given direction