Unit 6: Energy, Work and Power Work Energy Theorem vs. Conservation of Energy

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Unit 6 Energy, Work and PowerWork Energy
Theorem vs. Conservation of Energy

• Monkemeier
• Enriched Physics

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Back in time . . Units 4 and 5 . .
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Back in Time Unit 5

• Impulse D Momentum
• Remember that the impulse was an EXTERNAL FORCE
  acting over a period of time to CHANGE an
  objects Momentum

• Momentum is Conserved
• When BOTH objects are taken into consideration
  then TOTAL Momentum BEFORE TOTAL Momentum AFTER
• Momentum is transferred from one object to the
  other.

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External Force vs. Internal Force
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Work Energy Theorem vs. Conservation of Energy

• Work Energy Theorem
• WORK done on/by an OBJECT will CHANGE the ENERGY
  of the OBJECT.
• Work Force x displacement

• Energy Conservation
• Total Energy BEFORE MUST EQUAL Total ENERGY
  after.
• Gravitational Potential Energy (GPE) goes to
  Kinetic Energy (KE) when an object is dropped.

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Work
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Work
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Work Force x displacement

• What unit will work have?
• How is this unit derived?
• How does the unit for work compare to the unit
  for energy?