Mission NL1 Inertia and Newton's First Law

The law of inertia (Newton's first law) applies ...

An object at rest will tend to stay at rest; an object in motion will tend to stay in motion with the same speed and direction, unless acted upon by an unbalanced force.

Examine Newton's first law as written in the Know the Law section. Pull the sentence apart piece by piece and carefully reflect upon its meaning. Observe that there are two parts to the first law - one which applies to stationary objects and the other which applies to moving objects.