Science 7
Notes 27
Balanced Force
Unbalanced Force
Newton
Inertia
Friction
What is force?
Give an example
of an action that
is a force.
What affect does
force have on
motion?
Explain balanced
forces.
Describe the difference
between balanced and
unbalanced forces.
Explain Newton’s first
law of motion (inertia).
Remember that a force is…
A lift, push, pull, etc…
Causes change in an objects motion, shape, or energy level
Balanced Forces:
– Equal in strength but opposite in direction
– Object will not accelerate
What affect will a
balanced force
have on an
object?
Explain
unbalanced
forces.
What affect will
an unbalanced
force have on an
object?
What is the unit
of measurement
for force?
Unbalanced Force:
– A greater force is applied in one direction
– Causes object to accelerate
Force is measured in Newtons (one Newton is about the same amount of
force needed to hold up one stick of butter)
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Science 7
Notes 27
Sir Isaac Newton’s 1 Law of Motion
“Inertia”
st
Describe
Newton’s first
law of motion
(inertia).
What is inertia?
Why is a seat belt
considered to be
an “anti-inertia”
device?
An object at rest tends to stay at rest, while an object in motion tends to stay
in motion unless acted upon by an unbalanced force.
Inertia: an objects tendency to maintain its motion
• A seat belt is an “anti-inertia” devices
because it will stop the motion of a person
Friction is an anti-inertia force that slows an object
down when two surfaces are rubbed together
What is friction?
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