Thermodynamics Questions and Answers – Displacement Work and Indicator Diagram

«
»

This set of Thermodynamics Multiple Choice Questions & Answers (MCQs) focuses on “Displacement Work and Indicator Diagram”.

1. Macroscopic properties p and V are significant only for
a) equilibrium states
b) non-equilibrium states
c) depends on the state
d) none of the mentioned
View Answer

Answer: a
Explanation: This is true for at any intermediate point in the travel of piston.
advertisement

2. In a cylinder, infinitesimal amount of work done by the gas on piston is given by
a) F*dl
b) p*a*dl
c) p*dV
d) all of the mentioned
View Answer

Answer: d
Explanation: F=p*a and work equals force multiplied by displacement.

3. For a constant pressure process, work done is
a) zero
b) p*(V2-V1)
c) p1*V1*ln(V2/V1)
d) none of the mentioned
View Answer

Answer: b
Explanation: Work done in a process is given by the area under p-dV graph.
advertisement
advertisement

4. For a constant volume process, work done is
a) zero
b) p*(V2-V1)
c) p1*V1*ln(V2/V1)
d) none of the mentioned
View Answer

Answer: a
Explanation: Work done in a process is zero since volume remains constant.

5. For a process in which pV=C, work done is
a) zero
b) p*(V2-V1)
c) p1*V1*ln(V2/V1)
d) none of the mentioned
View Answer

Answer: c
Explanation: Work done is given by integral of (p*dV) from V1 to V2.
advertisement

6. The area of the indicator diagram represents the magnitude of the
a) net heat transfer by the system
b) net work done on the system
c) net work done by the system
d) none of the mentioned
View Answer

Answer: c
Explanation: It is the work done in one engine cycle.

7. For Pm=(Ad/Ld)*K, which of the following is true?
a) Pm=mean effective pressure
b) Ad and Ld are area of diagram and length of diagram respectively
c) K id the indicator spring constant
d) all of the mentioned
View Answer

Answer: d
Explanation: This formula comes from the indicator diagram.
advertisement

8. For a two-stroke engine, work done in one minute is given by
a) PmALN
b) PmALN/2
c) 2PmALN
d) none of the mentioned
View Answer

Answer: a
Explanation: In a two-stroke cycle, the engine cycle is completed in two strokes of the piston.

9. The power available at crankshaft is always _____ indicated power.
a) more
b) less
c) equal
d) none of the mentioned
View Answer

Answer: b
Explanation: Due to friction.
advertisement

10. Mechanical efficiency of engine is given by
a) IP/BP
b) 1/(BP*IP)
c) (BP*IP)
d) BP/IP
View Answer

Answer: d
Explanation: Brake power is less than indicated power and mechanical efficiency is given by BP/IP.

11. An engine is said to be double-acting, if the working fluid is made to work on both sides of the piston.
a) true
b) false
View Answer

Answer: a
Explanation: Such an engine develops twice the amount of work developed in a single-acting engine.

Sanfoundry Global Education & Learning Series – Thermodynamics.
To practice all areas of Thermodynamics, here is complete set of 1000+ Multiple Choice Questions and Answers.

Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

advertisement
advertisement
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer & SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage, Advanced C Programming, SAN Storage Technologies, SCSI Internals & Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him @ LinkedIn | Youtube | Instagram | Facebook | Twitter