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Using the formula Efficiency = WorkOut/EnergyIn, the effieciency is 0.190. The correct percent answer is therefore 19.0. Both energy values must be expressed in the same units in the equation.

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Calculating Heat Engine Effieciency

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The efficiency of a heat engine is simply a comparison of work output and energy input:

Percent Efficiency = (WorkOutput/Energyinput)*100

Textbook Discussion: Sections 7.14, pages 236. See Also: Figure 7.14, pages 239.

Problem

What is the percent efficiency of a heat transfer engine like a steam engine that consumes 41.3 calories of heat in order to do 32.8 joules of work? Given: 4.18 J/cal

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Calculating Heat Engine Effieciency

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Problem

"Will you walk into my parlour?" said the Spider to the Fly,
"'Tis the prettiest little parlour that ever you did spy..."
Mary Howitt-1834

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Calculating Heat Engine Effieciency

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Problem

"Will you walk into my parlour?" said the Spider to the Fly,"'Tis the prettiest little parlour that ever you did spy..."Mary Howitt-1834

"Will you walk into my parlour?" said the Spider to the Fly,
"'Tis the prettiest little parlour that ever you did spy..."
Mary Howitt-1834