A square steel bar of side length w= 0.13 m has a thermal conductivity of k= 14 J/(s m. °C) and is L= 2.1 m long. One end is placed near a blowtorch so that the temperature is T= 78° C while the other end rests on a block of ice so that the temperature is a constant T2 (a) Input an expression for the heat transferred to the cold end of the bar as a function of time, using A= w as the cross-sectional area of the bar. (b) How much energy, in joules, was conducted in 1 hour, assuming T2 = 0° C? (c) Input an expression for the mass of the water melted in 1 hour using Q, from above and Lfthe latent heat of fusion.

A square steel bar of side length w= 0.13 m has a thermal conductivity of k= 14 J/(s m. °C) and is L= 2.1 m long. One end is placed near a blowtorch so that the temperature is T= 78° C while the other end rests on a block of ice so that the temperature is a constant T2 (a) Input an expression for the heat transferred to the cold end of the bar as a function of time, using A= w as the cross-sectional area of the bar. (b) How much energy, in joules, was conducted in 1 hour, assuming T2 = 0° C? (c) Input an expression for the mass of the water melted in 1 hour using Q, from above and Lfthe latent heat of fusion.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter17: Energy In Thermal Processes: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 67P

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