(a)
The efficiency of a diesel engine
(a)
Answer to Problem 24PQ
The efficiency of a diesel engine is given by
Explanation of Solution
Write the expression to calculate efficiency of the diesel engine.
Here,
Write the expression for the energy when heat enters the engine from the hot reservoir through isobaric process
Here,
Write the expression for the energy when heat leaves the engine to the cold reservoir through isochoric process
Here,
For an adiabatic process at
Here,
For an adiabatic process at
Here,
Write the expression for specific heat capacity.
Substitute (II), (III) in (I).
Substitute (IV), (V), (VI) in (VII).
At
Conclusion:
Substitute (IX) in (VIII).
Hence, the efficiency of a diesel engine is given by
(b)
The efficiency of the diesel engine represented by Figure P22.24.
(b)
Answer to Problem 24PQ
The efficiency of the diesel engine is
Explanation of Solution
Rewrite (X).
Use
Conclusion:
Substitute
Therefore, the efficiency of the diesel engine is
Want to see more full solutions like this?
Chapter 22 Solutions
EBK WEBASSIGN FOR KATZ'S PHYSICS FOR SC
- Figure P22.73 illustrates the cycle ABCA for a 2.00-mol sample of an ideal diatomic gas, where the process CA is a reversible isothermal expansion. What is a. the net work done by the gas during one cycle? b. How much energy is added to the gas by heat during one cycle? c. How much energy is exhausted from the gas by heat during one cycle? d. What is the efficiency of the cycle? e. What would be the efficiency of a Carnot engine operated between the temperatures at points A and B during each cycle?arrow_forwardFigure P21.37 shows a PV diagram for a gas that is compressed from Vi to Vf. Find the work done by the a. gas and b. environment during this process. Does energy enter the system or leave the system as a result of work? FIGURE P21.37arrow_forward(a) Determine the work done on a gas that expands from i to f as indicated in Figure P19.16. (b) What If? How much work is done on the gas if it is compressed from f to i along the same path? Figure P19.16arrow_forward
- A thermodynamic cycle is shown in Figure P21.34 for a gas in a piston. The system changes states along the path ABCA. a. What is the total work done by the gas during this cycle? b. How much heat is transferred? Does heat flow into or out of the system? Figure P21.34arrow_forwardA biology laboratory is maintained at a constant temperature of 7.00C by an air conditioner, which is vented to the air outside. On a typical hot summer day, the outside temperature is 27.0C and the air-conditioning unit emits energy to the outside at a rate of 10.0 kW. Model the unit as having a coefficient of performance (COP) equal to 40.0% of the COP of an ideal Carnot device. (a) At what rate does the air conditioner remove energy from the laboratory? (b) Calculate the power required for the work input. (c) Find the change in entropy of the Universe produced by the air conditioner in 1.00 h. (d) What If? The outside temperature increases to 32.0C. Find the fractional change in the COP of the air conditioner.arrow_forwardA sample of a monatomic ideal gas is contained in a cylinder with a piston. Its state is represented by the dot in the PV diagram shown in Figure OQ18.9. Arrows A through E represent isobaric, isothermal, adiabatic, and isovolumetric processes that the sample can undergo. In each process except D, the volume changes by a factor of 2. All five processes are reversible. Rank the processes according to the change in entropy of the gas from the largest positive value to the largest-magnitude negative value. In your rankings, display any cases of equality. Figure OQ18.9arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
- College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax CollegePhysics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning