Newton

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Newtons Third Law Readings Chapter 8
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Newtons Third Law
When you have more than 1 system the
Newtons Third Law can provide an additional
information about the forces.
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Newtons Third Law
The force of the nail on the hammer
The force of the hammer on the nail
The Newtons Third Law
The forces (action-reaction pair) have
opposite direction and the same magnitude
They (action-reaction pair) never occur on
the same object
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Newtons Third Law
Two systems Person and Crate
The Newtons Third Law

• Equilibrium
• System P
• System C
• System PC

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Newtons Third Law
Two systems Rope and Safe
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Newtons Third Law
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Find tension of rope 2
No friction
System A
System B
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Find tension of rope 2
No friction
System A
System B
Newtons Third Law
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Example Find acceleration of the lower block.
The coefficient of kinetic friction between the
lower block and the surface is 0.3. The
coefficient of kinetic friction between the lower
block and the upper block is 0.3.
Newtons Third Law
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Upper block
Lower block
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Upper block
Lower block
Unknown
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(No Transcript)
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Example The 10.2 kg block is held in place by
the massless rope passing over two massless,
frictionless pulleys. Find the tensions to
and the magnitude of force F.
The same rope
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Equilibrium
Equilibrium
Equilibrium
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Equilibrium