One end of a solid cylindrical copper rod 0.200 m long and 0.0250 m in radius is inserted into a large block of solid hydrogen at its melt- ing temperature, 13.84 K. The other end is blackened and exposed to thermal radiation from surrounding walls at 500.0 K. The sides of the rod are insulated, so no energy is lost or gained except at the ends of the rod. (a) When equilibrium is reached, what is the tem- perature of the blackened end? The thermal conductivity of copper at temperatures near 20 K is 1670 Wm • K. (b) At what rate (in kg/h) does the solid hydrogen melt?

One end of a solid cylindrical copper rod 0.200 m long and 0.0250 m in radius is inserted into a large block of solid hydrogen at its melt- ing temperature, 13.84 K. The other end is blackened and exposed to thermal radiation from surrounding walls at 500.0 K. The sides of the rod are insulated, so no energy is lost or gained except at the ends of the rod. (a) When equilibrium is reached, what is the tem- perature of the blackened end? The thermal conductivity of copper at temperatures near 20 K is 1670 Wm • K. (b) At what rate (in kg/h) does the solid hydrogen melt?

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 20.61AP: An aluminum rod 0.500 m in length and with a cross sectional area of 2.50 cm2 is inserted into a...

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