67 l allM O 2 o 9:05the test.pdfQ1/ The thermal contact conductance at the interface of two1.5-cm-thick copper plates is measured to be 19,000 W/m2 °C.Determine the thickness of the copper plate whose thermalresistance is equal to the thermal resistance of the interfacebetween the plates. The thermal conductivity of copper k = 401 W/m-°CQ2/ A 4-m-internal-diameter spherical tank made of 1.75-cm-thickstainless steel (k 15 W/m °C) is used to store iced water at 0°C. Thetank is located in a room whose temperature is 35°C. The walls of theroom are also at 35°C. The outer surface of the tank is black, and heattransfer between the outer surface of the tank and the surroundings is bynatural convection and radiation. The convection heat transfercoefficients at the inner and the outer surfaces of the tank are 80 W/m2°C and 10 W/m2 °C, respectively. Determine (a) the rate of heattransfer to the iced water in the tank and (b) the amount of ice at 0°Cthat melts during a 1-h period. The heat of fusion of water atatmospheric pressure is hif 334 kJ/kg.

Given Thermal conductivity, k = 401 W/mK Heat transfer coefficient, h = 19000 W/m2K

Q1/ The thermal contact conductance at the interface of two 1.5-cm-thick copper plates is measured to be 19,000 W/m2· °C. Determine the thickness of the copper plate whose thermal resistance is equal to the thermal resistance of the interface between the plates. The thermal conductivity of copper k = 401 W/n %3D

Q1/ The thermal contact conductance at the interface of two 1.5-cm-thick copper plates is measured to be 19,000 W/m2· °C. Determine the thickness of the copper plate whose thermal resistance is equal to the thermal resistance of the interface between the plates. The thermal conductivity of copper k = 401 W/n %3D

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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