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Now we come
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to Newton's third law.
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“If one object
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exerts a force on another,
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the other exerts the same force
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in opposite direction on the one.“
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I read it again:
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“If one object exerts a force
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on another,
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the other exerts the same force in opposite direction
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on the one.”
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And I
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normally
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summarize that
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as follows
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the third law
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as action
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equals minus reaction.
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And the minus sign indicates then
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that it opposes.
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So you sit on your seats
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'n' you're pulled down on your seats,
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because of gravity,
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and the seats will push back on you
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with the same force.
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Action equals minus reaction.
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I held the baseball in my hand
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the baseball pushes on my hand
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with a certain force,
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I push on the baseball
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with the same force.
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I push against the wall
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with a certain force
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the wall pushes back
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in the opposite direction
with exactly the same force.
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The third law always holds.
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Whether the objects
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are moving or accelerated
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makes no difference.
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All moments in time
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the force – we call it actually the contact force –
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between two objects
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one on the other is always the same as the other on one
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but in the opposite direction.
