Concept explainers
(a)
Whether it is possible for heat to flow into the system if the temperature of the system is fixed and explain the same and specify the example of this process.
(a)
Answer to Problem 1CQ
Explanation of Solution
The formula to calculate the amount of heat is,
Here,
At constant temperature the change in the internal energy of the system is zero but when there is isothermal expansion the work is done by the system is positive work. The net work done by the system is having a positive value due to which the total heat have a positive value that is the heat flows into the system. The example of such an instance is the isothermal expansion of the gas.
Conclusion
Therefore, it is possible to have a substance of a fixed temperature in which the heat flows into the system and the example of this process is isothermal expansion.
(b)
Whether it is possible for heat to flow out of the system if the temperature of the system is fixed and explain the same and specify the example of this process.
(b)
Answer to Problem 1CQ
Explanation of Solution
The formula to calculate the amount of heat is,
At constant temperature the change in the internal energy of the system is zero but when there is isothermal compression the work is done on the system in a negative direction. The net work done by the system is having a negative value due to which the total heat have a negative value that is the heat flows out of the system. The example of such an instance is the isothermal compression of the gas.
Conclusion
Therefore, it is possible to have a substance of a fixed temperature in which the heat flows out of the system and example of this process isothermal compression.
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Chapter 18 Solutions
Physics (5th Edition)
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