Concept explainers
(a)
The rate at which all the three motors are using the electrical energy.
(a)
Answer to Problem 9PEA
The rate at which all the three motors are using the electrical energy is
Explanation of Solution
Write the expression for the total power.
Here,
Conclusion:
Determine the power of the fan motor for blowing air over the inside cooling coils in Watt.
Determine the power of the fan motor for blowing air over the outside condenser coils in Watt.
Determine the power of the compressor motor in Watt.
Substitute
Therefore, the rate at which all the three motors are using the electrical energy is
(b)
The cost of running the unit per hour.
(b)
Answer to Problem 9PEA
The cost of running the unit per hour is
Explanation of Solution
Write the expression for the cost of running the unit per hour.
Here,
Conclusion:
Substitute
Therefore, the cost of running the unit per hour is
(c)
The cost of running the unit for
(c)
Answer to Problem 9PEA
The cost of running the unit is $118.80.
Explanation of Solution
Write the expression for the cost of running the unit.
C = ct
Here, C is the cost and t is the operation time.
Conclusion:
Calculate the total operation time.
Substitute $0.33/h for c and 360 h for t in the above equation to find the cost.
Therefore, the cost of running the unit is $118.80.
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Chapter 6 Solutions
Integrated Science
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