Thermodynamics Questions and Answers – Maxwell’s Equations and TDS Equations

«
»

This set of Thermodynamics Problems focuses on “Maxwell’s Equations and TDS Equations”.

1. If a relation exists among variables x,y,z then z may be expressed as a function of x and y as, dz=Mdx+Ndy .
a) true
b) false
View Answer

Answer: a
Explanation: Here, M,N and z are functions of x and y.
advertisement

2. A pure substance which exists in a single phase has ____ independent variables.
a) zero
b) one
c) two
d) three
View Answer

Answer: c
Explanation: Of all the quantities, any one can be expressed as a function of any two others.

3. Which of the following relation is correct?
a) dU=TdS-pdV
b) dH=TdS+Vdp
c) dG=Vdp-SdT
d) all of the mentioned
View Answer

Answer: d
Explanation: These relations are true for a pure substance which undergoes an infinitesimal reversible process.
advertisement
advertisement

4. Maxwell’s equations consists of ____ equations.
a) four
b) three
c) two
d) one
View Answer

Answer: a
Explanation: Maxwell’s equations consists of four equations.

5. Which of the following is not a Maxwell equation?
a) (∂T/∂V) = -(∂p/∂S)
b) (∂T/∂p) = -(∂V/∂S)
c) (∂p/∂T) = (∂S/∂V)
d) (∂V/∂T) = -(∂S/∂p)
View Answer

Answer: b
Explanation: The correct equation is (∂T/∂p) = (∂V/∂S).
advertisement

6. The condition for exact differential is
a) (∂N/∂y) = (∂M/∂x)
b) (∂M/∂y) = (∂N/∂x)
c) (∂M/∂y) = -(∂N/∂x)
d) all of the mentioned
View Answer

Answer: b
Explanation: This is the condition for perfect or exact differential and here M and N are the functions of x and y.

7. The first TdS equation is
a) TdS=Cv*dT + T(∂T/∂p)dV
b) TdS=Cv*dT – T(∂p/∂T)dV
c) TdS=Cv*dT + T(∂p/∂T)dV
d) TdS=Cv*dT – T(∂T/∂p)dV
View Answer

Answer: c
Explanation: This equation comes when entropy is defined as a function of T and V and using Cv and Maxwell’s third equation.
advertisement

8. The second TdS equation is
a) TdS=Cp*dT + T(∂V/∂T)dp
b) TdS=Cp*dT – T(∂V/∂T)dp
c) TdS=Cp*dT + T(∂T/∂V)dp
d) TdS=Cp*dT – T(∂T/∂V)dp
View Answer

Answer: b
Explanation: This equation comes when entropy is defined as a function of T and p and using Cp and Maxwell’s fourth equation.

9. Which of the following is true?
a) (∂p/∂V)*(∂V/∂T)*(∂T/∂p)= infinity
b) (∂p/∂V)*(∂V/∂T)*(∂T/∂p)= 0
c) (∂p/∂V)*(∂V/∂T)*(∂T/∂p)= 1
d) (∂p/∂V)*(∂V/∂T)*(∂T/∂p)= -1
View Answer

Answer: d
Explanation: This is the relation between the thermodynamic variables, p,V and T.
advertisement

10. For getting TdS equations, we assume entropy to be a function of T and V and also of T and p.
a) true
b) false
View Answer

Answer: a
Explanation: For first TdS equation, we assume entropy as a function of T and V and for second TdS equation, we assume entropy as a function of T and p .

Sanfoundry Global Education & Learning Series – Thermodynamics.
To practice problems on 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