T

(a) Q ^ 0 for the irreversible process

(c) The irreversible process cannot perform work

1.6 Describe a version of each of the four processes in Prob. 1.1 that is closer to reversible than the original process.

1.7 One mole of air is changed from state #1 (580 K, 17 atm) to state #2 (380 K, 8 atm) by two paths, both consisting of two parts.

Path A: proceeds from state #1 isothermally to state #3, then isobarically to state #2. Path B: adiabatic expansion to state #4 followed by constant-volume cooling to state #2.

During the adiabatic expansion from state #1 to state #4, the temperature and pressure are related by:

The portion of path B from state #4 to state #2 is linear on a p - T diagram.

(a) determine T4 and p4 and plot the two paths on a p - T diagram.

(b) what is the molar volume at state #2?

(c) determine the changes in internal energy between state #1 and states #2, 3 and 4. Air is an ideal gas, and its thermal equation of state is:

where R is the gas constant.

(d) Calculate the heat and work for each stage and complete the 2nd, 3rd and 4th columns of the following table. Express Au, Q and W in Joules.

Path

Au

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Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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