Q.1) chose the correct answer1. The effective thermal conductivity varies with thea) Porosity or void fraction of the medium,b) depends on the thermal conductivities of each of the phases,c) The detailed solid phase geometry,d) All of those (a, b, and c)2. The temperature distribution associated with radial conduction through acylindrical wall is ......a) logarithmic behave, b) linear behavec) None of theses3. The critical insulation radius in radial conduction is.....a) rc = h/k,b) Ter = k/h4. The thermal conductivity of a sheet of rigid, extruded insulation is reportedto be k = 0.029 W/m. K. The measured temperature difference across a 20-mm-thick sheet of the material is T₁ T₂ = 10°C. The heat flux and heat ratethrough a 2 m x 2 m sheet of the insulation isa) 10.5 W/m² and 68 WKAc) 16.5 W/m² and 48 Wb) 13.5 W/m² and 29 Wd) 14.5 W/m² and 58 Wc) None of these5. For one-dimensional, steady-state conduction in a plane wall with no heatgeneration and constant thermal conductivity, the temperaturea. varies exponential with x axis,b) varies linearly with x- axis,c) varies randomly with x-axis6. Radiation heat transfer needs a media to occur where as conduction andconvection is not.a) Yes,b) No7. The heat flux from a wall to air in motion having a heat transfer coefficientof 25 W/m². K and exposed to a temperature difference of 15 °C isa) 1.67 W, b) 375 W,c) 15 W,d) 25 W8. Radiation transfer occurs most efficiently in vacuum.a) Yes,b) No9. Convection heat transfer occurs between aa) fluid at rest and a bounding surface when the two are at differenttemperatures.b) fluid in motion and a bounding surface when the two are at differenttemperatures.c) solid and a bounding surface when the two are at differenttemperatures.d) two fluids at rest when the two are at different temperatures.10. Conduction heat transfer occurs(a) due to a temperature difference through a stationary gas.(b) due to a temperature difference through a solid.(c) due to a temperature difference through a stationary liquid.(d) all of these

The correct answer. “Since you have posted multiple questions, we will provide the…

Q.1) chose the correct answer 1. The effective thermal conductivity varies with the a) Porosity or void fraction of the medium, b) depends on the thermal conductivities of each of the phases, c) The detailed solid phase geometry, d) All of those (a, b, and c)

Q.1) chose the correct answer 1. The effective thermal conductivity varies with the a) Porosity or void fraction of the medium, b) depends on the thermal conductivities of each of the phases, c) The detailed solid phase geometry, d) All of those (a, b, and c)

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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