Force, Mass, and Acceleration
Review
Force
____________________________
Force
 Force causes an object to begin to
move,
direction.
stop moving, or change
Acceleration
 Acceleration is
___________________
Acceleration
 Acceleration is an increase in speed,
decrease in speed, or change in
direction.
Mass
 Mass is
________________________
Mass
Mass is the amount of matter in
an object.
Newton’s Second Law of
Motion
 Newton’s Second Law of Motion
explains how force, mass, and
acceleration are related. It states that
the net force on an object is equal to
the product of its acceleration and its
mass
 Force = Mass x Acceleration
Newton
 When acceleration is measured in
meters per second per second and
mass is measured in kilograms, force
is measured in kilograms x meters per
second per second. This long unit of
measure is called the Newton (N).
 The Newton is named in honor of
Isaac Newton.
 One newton equals the force required to
accelerate one kilogram of mass at 1
meter per second per second.
 The formula is
1N = 1 kg x 1m/s
Try it…
 If you have a 52 kg water skier who is
being pulled by a speedboat and her
acceleration is 2 meters/second/second, all
we need to do is substitute mass and
acceleration.
Force = 52kg x
104N
Mass x
Force
2 m/s =
Acceleration
=
Changes in Force
 Suppose you are pulling a wagon full of
rocks and you want to increase the
acceleration (speed) of the wagon. You
can do one of two things. You can
increase the amount of force used to
pull the wagon (pull harder) or decrease
the amount of mass (take some of the
rocks out of the wagon).
 Suppose you are pushing your
younger brother/sister on a small
bicycle and it is going too fast. You
would want to decrease the
acceleration (slow it down) by doing
one of two things. You can decrease
the amount of force (don’t push as
hard) you use to push the wagon or
increase the amount of mass (add
another child).
Examples
 Read your paper and based on what
we just talked about, answer the
questions.