force
a push or a pull exerted on an object in order to change the motion of the object
static friction
The force that resists the start of sliding motion between two surfaces that are touching
kinetic friction
The force that resists the movement of two surfaces that are touching and are moving relative to each other.
drag
A friction-like force that opposes the motion of an object in a fluid
field
When a force acts at a distance, the area in which an object experiences that force
net force
The combination of all of the forces acting on an object
magnitude
strength of a force
inertia
The tendency of an object to resist a change in motion unless an outside force acts on the object
newton
unit used to express force
Newton's First Law
law of inertia. An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Newton's Second Law
Force = mass x acceleration
Newton's Third Law
Objects Exert a Force on Each Other, Forces in Pairs Have Equal Size but Opposite Directions, Forces Acting in Pairs Can Have Unequal Effects, Forces Can Act in Multiple Pairs
balanced force
a net force of zero
unbalanced forces
Forces that produce a nonzero net force, which changes an object's motion
100 N to the left
What is the net force in the image?
0 N
What is the net force in the image?