(a)
The PV diagram for the cycle.
(a)
Answer to Problem 84P
The required PV diagram is shown in Figure 1.
Explanation of Solution
Formula:
The range of the isobaric expansion cycle is given by,
The range of the adiabatic compression cycle is given by,
The range for the isobaric compression cycle is given by,
The range of the adiabatic expansion cycle is given by,
Calculation:
The state functions A for the PV graph are given by,
The state functions B for the PV graph are given by,
The state functions C for the PV graph are given by,
The state functions D for the PV graph are given by,
The required PV diagram is shown in Figure 1
Figure 1
Conclusion:
Therefore, the required PV diagram is shown in Figure 1
(b)
The expression for the coefficient of performance.
(b)
Answer to Problem 84P
The value of
Explanation of Solution
Formula Used:
The expression for the coefficient of performance is given by,
The expression for
The expression for the value of
The expression for the work done during the cycle is given by,
The expression for the heat released in the entire cycle is given by,
The expression to determine the value of
The expression to determine the value of
Calculation:
The expression for the value of the
The difference between the value of
The value of
Conclusion:
Therefore, the value of
(c)
The coefficient of performance of the refrigerator.
(c)
Answer to Problem 84P
The value of value of
Explanation of Solution
Given:
The volume
The initial pressure
The volume
The temperature
The pressure ratio
Formula:
The expression for the temperature and the pressure after adiabatic process BC is given by,
The expression for the temperature and the pressure after adiabatic process DA is given by,
From above and from equation (1) the value of
The expression for
Calculation:
The value of
Conclusion:
Therefore, the value of
(d)
The electrical energy that must be supplied to the motor of rotor is given by,
(d)
Answer to Problem 84P
The electrical energy that must be supplied is
Explanation of Solution
Given:
The rate
Formula:
The expression to determine the electrical energy that must be supplied is given by,
Calculation:
The electrical energy that must be supplied is calculated as,
Conclusion:
Therefore, the electrical energy that must be supplied is
(e)
The amount added to the monthly electricity bill.
(e)
Answer to Problem 84P
The electrical energy that must be supplied is
Explanation of Solution
Given:
The number of days
The time for which the motor runs is
The charge
Formula:
The amount of electrical energy utilized by the refrigerator per month is given by,
Calculation:
The electrical energy utilized by the refrigerator per month is calculated as,
Conclusion:
Therefore, the electrical energy that must be supplied is
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Chapter 19 Solutions
Physics For Scientists And Engineers Student Solutions Manual, Vol. 1
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