| 6C-1 : | Is This a Perpetual Motion Machine ? | 2 pts |
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| In a day, an electrical resistance heater uses 8.4 kW-h of electricity. In the same day, the heater delivers 9.7 kW-h of heat to the house in which it is located. Is this possible or is this a perpetual motion machine? | ||||||||||||||||||
| If so, what kind? Explain your reasoning. | ||||||||||||||||||
| Read : | Short and sweet. | |||||||||||||||||
| Given: | Ws | 8.4 | kW-h | Find: | Is this a PMM ? Explain | |||||||||||||
| QH | 9.7 | kW-h | ||||||||||||||||
| Diagram: | 
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| Assumptions: | None. | |||||||||||||||||
| Equations / Data / Solve: | ||||||||||||||||||
| Apply the 1st Law to the inventor's process : | ||||||||||||||||||
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Eqn 1 | |||||||||||||||||
| But 8.4 kW-h ¹ 9.7 kW-h ! | ||||||||||||||||||
| Therefore, if the device operates on a true thermodynamic cycle (no change in state after a complete cycle), then it violates the 1st Law. | ||||||||||||||||||
| Verify: | No assumptions to verify ! | |||||||||||||||||
| Answers : | It is a PMM of the 1st Kind ! | |||||||||||||||||
