In an experiment to determine the thermal conductivity of a new metal alloy, a bar of the metal is completely surrounded by insulation and exposed to 707 W of constant heat energy at one end. The bar has a radius of 0.074 m and a length of 0.331 m. The entire set-up is place in a cold room and once the system has reached steady state conditions, the temperature at the hot end is measured to be 63.8°C and the temperature at the cold end is measured to be 14.9°C. What is the thermal conductivity (in W/m∙K) of the metal alloy [round your final answer to zero decimal places]?

In an experiment to determine the thermal conductivity of a new metal alloy, a bar of the metal is completely surrounded by insulation and exposed to 707 W of constant heat energy at one end. The bar has a radius of 0.074 m and a length of 0.331 m. The entire set-up is place in a cold room and once the system has reached steady state conditions, the temperature at the hot end is measured to be 63.8°C and the temperature at the cold end is measured to be 14.9°C. What is the thermal conductivity (in W/m∙K) of the metal alloy [round your final answer to zero decimal places]?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 71PQ

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In an experiment to determine the thermal conductivity of a new metal alloy, a bar of the metal is completely surrounded by insulation and exposed to 707 W of constant heat energy at one end. The bar has a radius of 0.074 m and a length of 0.331 m. The entire set-up is place in a cold room and once the system has reached steady state conditions, the temperature at the hot end is measured to be 63.8°C and the temperature at the cold end is measured to be 14.9°C. What is the thermal conductivity (in W/m∙K) of the metal alloy [round your final answer to zero decimal places]? Another metal alloy was tested using the same set-up (same size and heat input) as question above. If the temperature difference between the hot end and the cold end for this test was found to be 30°C, it would indicate that this material is a better conductor of heat than the material tested in question above.
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