(a)
The number of liters of fuel gasoline engine consumes in
(a)
Answer to Problem 6P
The number of liters of fuel gasoline engine consumes in
Explanation of Solution
Write the expression for the input energy of the gasoline for a particular time interval.
Here,
Conclusion:
It is given that, operating frequency of the engine is
Substitute
It is given that heat of combustion of the fuel is equal to
Calculate the number of liters of fuel consumed in
Here,
Therefore, the liters of fuel gasoline engine consumes in
(b)
The mechanical power output of the engine.
(b)
Answer to Problem 6P
The mechanical power output of the engine is
Explanation of Solution
Write the expression for the energy taken from the hot reservoir using first law of
Here,
Divide above equation by time for continuous-transfer process.
Here,
Write the expression for the power output.
Here,
Substitute
Conclusion:
Substitute
Therefore, the mechanical power output of the engine is
(c)
The torque exerted by the crankshaft on the load.
(c)
Answer to Problem 6P
The torque exerted by the crankshaft on the load is
Explanation of Solution
Write the expression for the power output of the engine in terms of the torque exerted by the crankshaft on the load.
Here,
Rearrange above equation to get
Conclusion:
Substitute
Therefore, the torque exerted by the crankshaft on the load is
(d)
The power the exhaust and cooling system must transfer out of the engine.
(d)
Answer to Problem 6P
The power the exhaust and cooling system must transfer out of the engine is
Explanation of Solution
Write the expression for the power transfer of exhaust and cooling system.
Here,
Conclusion:
It is given that, frequency of revolution of the crankshaft is
Calculate the energy exhausted in
Substitute
Therefore, the power the exhaust and cooling system must transfer out of the engine is
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Chapter 22 Solutions
Physics For Scientists And Engineers With Modern Physics, 9th Edition, The Ohio State University
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