Thermodynamics heat engine Question

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SUMMARY

The discussion centers on a thermodynamics problem involving a 1500 kW heat engine operating at 25% efficiency. The heat expelled is absorbed by water flowing at 60 L/s, which enters the cooling coils at 20 degrees Celsius. The calculated increase in temperature of the water is 4.48 degrees Celsius, while the textbook states it should be 18 degrees Celsius. The discrepancy arises from the need to convert the flow rate from liters to mass flow rate using the density of water.

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  • Understanding of thermodynamics principles, specifically heat engines
  • Familiarity with the equation mCΔT = Q for heat transfer calculations
  • Knowledge of unit conversions, particularly between liters and kilograms for water
  • Basic proficiency in algebra for solving equations
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Homework Statement


A 1500kW heat engine operates at 25% efficiency. The heat energy expelled at the low temperature is absorbed by a stream of water that enters the cooling coils at 20 degrees C. If 60L flows across the coils per second, determine the increase in temperature of the water.

Homework Equations


mCdeltaT = Q

The Attempt at a Solution


0.75*(1500Kj/s)(1000J/1kJ)(s/60L)(kgdegreesC/4186J) = 4.48
The book says that it is 18 degrees C. The DA that I did cancels out correctly though.

Thanks.
 
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You need to convert the 60L/s to mass flow rate in kg/s, you would need to find how many kg is in 1 L.
 
It's water, so with a density of 1, the answer should still be what I got.
 

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