Q2 A 2 kW resistance heater wire with thermal conductivity of k = 20 W/m °C, adiameter of D = 5 mm, and a length of L= 0.7 m is used to boil water. If the outersurface temperature of the resistance wire is Ts= 110°C, determine the temperature at thecenter of the wire.Q3: Consider a 20-cm-thick large concrete plane wall (k = 0.77 W/m °C) subjected toconvection on both sides with T1 = 27°C and h₁ = 5 W/m² °C on the inside, and T2 =8°C and h₂ = 12 W/m² °C on the outside. Assuming constant thermal conductivity withno heat generation and negligible radiation, (a) express the differential equations and theboundary conditions for steady one-dimensional heat conduction through the wall, (b)obtain a relation for the variation of temperature in the wall by solving the differentialequation, and (c) evaluate the temperatures at the inner and outer surfaces of the wall.Ans: (a)Ans: 121.4 °CdT (L)-kdx-=h₂ [T(L)-T₂](b) T(x) = 20-45.44xQ4: A double pane window consists of 3 mm thick layer of glass separated by a 12 mm widestagnant air space. for specified indoors and outdoors and outdoors temperatures, determine therate of the heat loss through the window and the inner surface temperature of the window.Take kglass = 0.78 W/m °C and Kair= 0.026 W/m °CAns: 114 W, 19.2 °C(c) 10.9°34Air

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Q2 A 2 kW resistance heater wire with thermal conductivity of k = 20 W/m °C, a diameter of D = 5 mm, and a length of L = 0.7 m is used to boil water. If the outer surface temperature of the resistance wire is Ts = 110°C, determine the temperature at the center of the wire.

Q2 A 2 kW resistance heater wire with thermal conductivity of k = 20 W/m °C, a diameter of D = 5 mm, and a length of L = 0.7 m is used to boil water. If the outer surface temperature of the resistance wire is Ts = 110°C, determine the temperature at the center of the wire.

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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