Thermodynamics heat engine Question

AI Thread Summary
A 1500 kW heat engine with 25% efficiency expels heat that is absorbed by water flowing at 60 L/s. The calculation for temperature increase involves using the equation mCdeltaT = Q, where the mass flow rate must be converted from liters to kilograms. The initial calculation yielded an increase of 4.48 degrees C, but the textbook states the correct increase is 18 degrees C. The discrepancy suggests a need to verify the conversion and application of the specific heat capacity of water. Accurate calculations are crucial for determining the correct temperature change in the cooling process.
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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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