1) Consider a tank containing 1 m³ of water at 20 °C. The tank is perfectly insulated. There are two copper rods, which each have one end in the water and the other in a reservoir at a different temperature. The first rod is 1 m long and 0.1 m in diameter, and its other end is in a reservoir of liquid nitrogen at 77 K. The second rod is 0.5 m long and 0.05 m in diameter, and its other end is connected to a reservoir at 120 °C. After some time the water in the tank freezes. What is the temperature of the ice in the tank when it finally reaches steady state? [kcu = 400 W m²¹ K-¹] a) 0 °C b) -20 °C c) - 50 °C d) - 70 °C e) - 90 °C

1) Consider a tank containing 1 m³ of water at 20 °C. The tank is perfectly insulated. There are two copper rods, which each have one end in the water and the other in a reservoir at a different temperature. The first rod is 1 m long and 0.1 m in diameter, and its other end is in a reservoir of liquid nitrogen at 77 K. The second rod is 0.5 m long and 0.05 m in diameter, and its other end is connected to a reservoir at 120 °C. After some time the water in the tank freezes. What is the temperature of the ice in the tank when it finally reaches steady state? [kcu = 400 W m²¹ K-¹] a) 0 °C b) -20 °C c) - 50 °C d) - 70 °C e) - 90 °C

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 31PQ: Consider the latent heat of fusion and the latent heat of vaporization for H2O, 3.33 105 J/kg and...

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