THE PRACTICE STUDIO

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PRACTICE · MEMBERSIntermediate · Single correct

PRACTICE / Carnot efficiency

How much heat must an ideal engine absorb?

A reversible engine operates between reservoirs at 600 K and 300 K. It delivers 100 J of net work per cycle.

How much heat does it absorb from the hot reservoir per cycle?

Organize the givens & assumptions
  • Hot reservoir: 600 K
  • Cold reservoir: 300 K
  • Net work: 100 J

The engine is reversible and cyclic; the reservoir temperatures remain fixed.

  1. A50 J50\ \mathrm J
  2. B200 J200\ \mathrm J
  3. C100 J100\ \mathrm J
  4. D300 J300\ \mathrm J

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