An iron bar 2.0 cm x 3.0 cm x 10.0 cm at a temperature of 95 °C is dropped into a barrel of water at 25 °C. The barrel is large enough so that the water temperature rises negligibly as the bar cools. The rate at which heat is transferred from the bar to the water is given by the expression Q (J/min) = UA (T₁ - T…) where U = 0.05 J/(min cm °C)] is a (cm) is the exposed surface area of the bar, T₁, and T are the surface temperature of the bar and the water temperature, respectively. The heat capacity of the bar is 0.46 J/(g °C). Heat conduction in iron is rapid enough for the temperature T, to be considered uniform throughout the bar. a) Write an energy balance on the bar |M = (60 cm³)(7.7 g/cm³) = 462 g C₁ = 0.46 kJ/(kg.°C), T = 25°C = 0.050 J/(min-cm² °C) |4=2[(2)(3) +(2)(10) + (3)(10)]cm² = 112 cm²

An iron bar 2.0 cm x 3.0 cm x 10.0 cm at a temperature of 95 °C is dropped into a barrel of water at 25 °C. The barrel is large enough so that the water temperature rises negligibly as the bar cools. The rate at which heat is transferred from the bar to the water is given by the expression Q (J/min) = UA (T₁ - T…) where U = 0.05 J/(min cm °C)] is a (cm) is the exposed surface area of the bar, T₁, and T are the surface temperature of the bar and the water temperature, respectively. The heat capacity of the bar is 0.46 J/(g °C). Heat conduction in iron is rapid enough for the temperature T, to be considered uniform throughout the bar. a) Write an energy balance on the bar |M = (60 cm³)(7.7 g/cm³) = 462 g C₁ = 0.46 kJ/(kg.°C), T = 25°C = 0.050 J/(min-cm² °C) |4=2[(2)(3) +(2)(10) + (3)(10)]cm² = 112 cm²

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Description: An iron bar 2.0 cm x 3.0 cm x 10.0 cm at a temperature of 95 °C is dropped into abarrel of water at 25 °C. The barrel is large enough so that the water temperaturerises negligibly as the bar cools. The rate at which heat is transferred from the bart

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.28P

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