Solve Hard Thermodynamics Q: Find Water W/Q Ratio

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SUMMARY

The discussion centers on a challenging thermodynamics problem involving the calculation of the work done by water (W) relative to the heat absorbed (Q) when water is heated in an open pan at 1 atm pressure. The correct formula for work is established as W = P(Vf - Vi). However, there is confusion regarding the heat absorbed, with the user initially suggesting Q = cm delta T, which is incorrect. The appropriate term to use is c_p, the specific heat capacity at constant pressure, to accurately calculate Q.

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Dooh
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This question is considered one of the hardest in this chapter regarding thermodynamics. I spent countless time trying to figure it out but i was never close to the answer. The question is:

Water is heated in an open pan where the air pressure is 1atm. WAter remains a liquid but expanded by a small amount when it was heated. FIND THE RATIO OF WORK DONE BY WATER TO THE HEAD ABSOBED BY THE WATER.

So that means:

W / Q

where W = P(Vf - Vi)
but what's Q? I tried Q = cm delta T but i was wrong. if anyone can help me i'd appreciate it thanks.
 
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What is cm? Shouldn't you be using [itex]c_p[/itex]?
 

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