· Force—any push or pull (units: Newtons (N))
o
Usually, forces
are drawn as arrows acting on an
object.
· 
If there’s more than one force, you add them together—the
sum is called the net force.
2 4
2
+ =
·
Forces that are
equal in size and opposite in direction are called balanced forces.
o
The net force is 0
o
No motion occurs
§
the object does
not move (really, it does not 
change its motion)
· If the forces are unequal, they are called unbalanced forces.
o
The net force is not 0
o
Motion occurs
§ 
(really, the object’s motion changes)
