Carnot Heat Engine: Solve for Heat Expelled to Cold Res.

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SUMMARY

The discussion centers on the calculation of heat expelled by a Carnot heat engine operating between a hot reservoir at 63°C and a cold reservoir at -14°C. The engine absorbs 590 J of heat from the hot reservoir. The correct calculation for the heat expelled to the cold reservoir, using the Carnot equation Q_H/Q_C = T_H/T_C, reveals that the temperature of the cold reservoir must be accurately converted to Kelvin, resulting in Q_C being 504 J. The error arose from misreading the temperature due to formatting issues in the homework assignment.

PREREQUISITES
  • Understanding of the Carnot cycle and its efficiency principles
  • Knowledge of thermodynamic temperature conversion (Celsius to Kelvin)
  • Familiarity with the relationship between heat absorbed and expelled in thermodynamic systems
  • Ability to manipulate algebraic equations for problem-solving
NEXT STEPS
  • Study the principles of the Carnot cycle in thermodynamics
  • Learn about the implications of temperature scales in thermodynamic calculations
  • Explore the derivation of the Carnot efficiency formula
  • Practice solving problems involving heat transfer in thermodynamic systems
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Students studying thermodynamics, physics enthusiasts, and anyone preparing for exams involving heat engines and energy transfer calculations.

tehjojo
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Homework Statement



Consider a Carnot engine that operates between a hot reservoir at 63°C and a cold reservoir at -14°C. In running 25 minutes, this engine absorbs 590 J of heat from the hot reservoir.

How much heat does it expel to the cold reservoir?

Homework Equations


Q_H/Q_C = T_H/T_C

The Attempt at a Solution


T_H = 336k
T_C = 287k
Q_H/Q_C = T_H/T_C \longrightarrow 590/Q_C = 336/287
Solving for Q_C I get 504 J, however, this is not the correct answer. What am I missing?
 
Physics news on Phys.org
Are you sure Tc= 287 K? The cold reservoir is at -14 C
 
Wow. It happened that on the site my homework is on, the negative sign and the number were on different lines, so I totally missed it. Thank you very much.
 

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