Heat Transfer Questions and Answers – Thermal Conductivity of Different Materials

«
»

This set of tough Heat Transfer Questions focuses on “Thermal Conductivity Of Different Materials”.

1. What is the thermal conductivity of asphalt in W/m K?
a) 0.064
b) 0.063
c) 0.062
d) 0.061
View Answer

Answer: c
Explanation: Asphalt concrete has three main structural elements i.e. aggregates, binder and the contact layer between them. It is soft at high temperatures but brittle at low temperatures.

2. Which one is having the highest thermal conductivity?
a) Silver
b) Copper
c) Glass
d) Earth
View Answer

Answer: a
Explanation: Thermal conductivity of silver is 410 W/m degree while that of copper, glass and earth are 385 W/m degree, 0.75 W/m degree and 0.138 respectively.

3. What is the thermal conductivity of magnetite in W/m K?
a) 3.7
b) 3.8
c) 3.9
d) 4.0
View Answer

Answer: b
Explanation: This is having low thermal conductivity because of high intramolecular interactions between their outer edge molecules.
Note: Join free Sanfoundry classes at Telegram or Youtube
advertisement
advertisement

4. Which one is having the lowest thermal conductivity?
a) Furnace
b) Wool
c) Saw dust
d) Glass wool
View Answer

Answer: d
Explanation: Thermal conductivity of glass wool is 0.03 W/m degree while that of a furnace, wool and saw dust are 0.30 W/m degree, 0.052 W/m degree and 0.07 respectively.

5. What is the thermal conductivity of coal in W/m K?
a) 0.25
b) 0.26
c) 0.27
d) 0.28
View Answer

Answer: b
Explanation: Coal is composed primarily of carbon along with variable quantities of other elements such as hydrogen, sulfur, oxygen and nitrogen.
Take Heat Transfer Practice Tests - Chapterwise!
Start the Test Now: Chapter 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

6. What is the thermal conductivity of cotton in W/m K?
a) 0.03
b) 0.04
c) 0.05
d) 0.06
View Answer

Answer: d
Explanation: It is a soft material that grows in a protective capsule, around the seeds of cotton plants.

7. Which one is having the highest thermal conductivity?
a) Brass
b) Aluminum
c) Cast iron
d) Steel
View Answer

Answer: b
Explanation: Thermal conductivity of aluminum is 225 W/m degree while that of brass, cast iron and steel are 107 W/m degree, 55 W/m degree and 20 respectively.
advertisement

8. What is the thermal conductivity of apple in W/m K?
a) 0.513
b) 0.613
c) 0.713
d) 0.813
View Answer

Answer: a
Explanation: It is a sweet fruit that has very low thermal conductivity in order to prevent it from damage.

9. What is the thermal conductivity of ice in W/m K?
a) 1.55
b) 1.66
c) 1.77
d) 1.88
View Answer

Answer: d
Explanation: Frozen water in the form of an ordinary household ice cube. The white zone in the center is the result of tiny air bubbles.
advertisement

10. Which one is having the lowest thermal conductivity?
a) Ash
b) Ice
c) Freon
d) Water
View Answer

Answer: c
Explanation: Thermal conductivity of freon is 0.0083 W/m degree while that of ash, ice and water are 0.12 W/m degree, 2.25 W/m degree and 0.55 respectively.

Sanfoundry Global Education & Learning Series – Heat Transfer.

To practice tough questions on all areas of Heat Transfer, here is complete set of 1000+ Multiple Choice Questions and Answers.

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). 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!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & technical discussions at Telegram SanfoundryClasses.