Newtons Third Law of Motion

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Newtons Third Law of Motion

• Tiffany Mounts
• CITERA 2007
• RESA III

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Have you ever seen a shuttle launch?
Video from http//www.nasa.gov/multimedia/highligh
ts/index.html.
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Think About It

• What causes the forward motion of the rocket?

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What will we discuss?

• What is ?
• What are ?
• What is
  ?

motion
forces
Newtons Third Law of Motion
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What is motion?
Motion
is
The action or process of moving.
The action of changing place or position.
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What is a force?
force
A
is
a
or
a
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Forces Continued

• Forces always come in pairs.
• The size of the forces on the first object equals
  the size of the force on the second object.
• The pairs are called equal and opposite
  action-reaction force pairs.

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What is Newtons Third Law?

• For every

ACTION
there is an equal
REACTION
and opposite
!!
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Examples of Newtons Third Law
When a skeet shooter fires his shotgun at a clay
disc flying through the air, he experiences the
recoil upon the shotgun. The "kick" felt by the
shooter is the reaction force upon the shotgun
which is equal in magnitude to the force that
pushes the pellets.
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Example 2
The baseball forces the bat to the left the bat
forces the ball to the right. When the baseball
hits the bat, it is an action. Then the bat
pushes back on the ball which is a reaction.
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Example 3
A pitcher throws a baseball to his catcher. The
baseball pushes the catchers glove to the left
and the glove pushes the baseball back to the
right. The baseball is acting on the glove and
the glove is reacting.
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Example 4
A bowling ball pushes the pin to the left and in
return the pin pushes the bowling ball to the
right. The bowling ball is performing an action
and the pin is reacting.