At steady state, the temperature profile in a laminated system appears thus: (2) 2.1aterai I Materia! If Determine the thermal conductivity of II if the steady-state heat flux is 12.6 X 10 W m and conductivity of I is 52 W m K'. Describe the Normal (N-type) interactions of phonons in solids. Describe the U-process of heat transfer in solids. 4(3) (a) (b) DR.A.A. ADAC

At steady state, the temperature profile in a laminated system appears thus: (2) 2.1aterai I Materia! If Determine the thermal conductivity of II if the steady-state heat flux is 12.6 X 10 W m and conductivity of I is 52 W m K'. Describe the Normal (N-type) interactions of phonons in solids. Describe the U-process of heat transfer in solids. 4(3) (a) (b) DR.A.A. ADAC

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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4. (a) Let the ends of a copper rod 100 cm long be maintained at 0°C. Suppose that the center of the bar is heated to 75°C by an ex- ternal heat source and that this situation is maintained until a steady-state results. Find this steady-state temperature distri- bution. (b) At a time t 0 (after the steady-state of part a has been reached), let the heat source be removed. At the same instant, let the end = 0 be placed in thermal contact with a reservoir at 10°C, while the other end remains at 0°C. Find the temperature as a function of position and time. X = = (c) Plot u versus x for several values of t. Also plot u versus t for several values of x. (d) What limiting value does the temperature at the center of the rod approach after a long time? How much time must elapse before the center of the rod cools to within 1°C of its limiting value?
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