| 6C-1 : |
Is This a Perpetual Motion Machine ? |
2 pts |
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| An inventor claims to have developed a resistance heater that supplies 1.2 kW-h of energy to a room for each kW-h of electricity it consumes. Is this a reasonable claim or has the inventor developed a perpetual motion machine ? Explain. |
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| Read: |
Short and sweet. |
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| Given: |
Ws |
1 |
kW-h |
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Find : |
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QH |
1.2 |
kW-h |
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Is this a PMM ? Explain |
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| Assumptions: |
None. |
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| Diagram : |
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| Equations / Data / Solve : |
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Apply the 1st Law to the inventor's process : |
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Eqn 1 |
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But 1.2 kW-h ¹ 1 kW-h ! |
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Therefore, if the device operates on a true thermodynamic cycle (no change in state after a complete cycle), then it violates the 1st Law. |
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| Verify : |
No assumptions to verify ! |
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| Answer : |
It is a PMM of the 1st Kind ! |
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