a) What is forced convection? How does it differ from natural convection? Isconvection caused by winds forced or natural convection?b) What is external forced convection? How does it differ from internal forcedconvection? Can a heat transfer system involve both internal and external convectionat the same time? Give an example.c) In which mode of heat transfer is the convection heat transfer coefficient usuallyhigher, natural convection or forced convection? Why?d) Consider a hot baked potato. Will the potato cool faster or slower when we blow thewarin air coming from our lungs on it instead of letting it cool naturally in the coolerair in the room? Explain.e) What is the physical significance of the Nusselt number? How is it defined?f) When is heat transfer through a fluid conduction and when is it convection? For whatcase is the rate of heat transfer higher? How does the convection heat transfercoefficient differ from the thermal conductivity of a fluid?g) Define incompressible flow and incompressible fluid. Must the flow of acompressible fluid necessarily be treated as compressible?un

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a) What is forced convection? How does it differ from natural convection? Is convection caused by winds forced or natural convection? b) What is external forced conv How does it differ from internal forced stem involve both internal and external convection convection? Can a heat transi at the same time? Give an example. c) In which mode of heat transfer is the convection heat transfer coefficient usually higher, natural convection or forced convection? Why? d) Consider a hot baked potato. Will the potato cool faster or slower when we blow the warm air coming from our lungs on it instead of letting it cool naturally in the cooler air in the room? Explain. e) What is the physical significance of the Nusselt number? How is it defined? f) When is heat transfer through a fluid conduction and when is it convection? For what case is the rate of heat transfer higher? How does the convection heat transfer coefficient differ from the thermal conductivity of a fluid? g) Define incompressible flow and incompressible fluid. Must the flow of a compressible fluid necessarily be treated as compressible? un r. Luma

a) What is forced convection? How does it differ from natural convection? Is convection caused by winds forced or natural convection? b) What is external forced conv How does it differ from internal forced stem involve both internal and external convection convection? Can a heat transi at the same time? Give an example. c) In which mode of heat transfer is the convection heat transfer coefficient usually higher, natural convection or forced convection? Why? d) Consider a hot baked potato. Will the potato cool faster or slower when we blow the warm air coming from our lungs on it instead of letting it cool naturally in the cooler air in the room? Explain. e) What is the physical significance of the Nusselt number? How is it defined? f) When is heat transfer through a fluid conduction and when is it convection? For what case is the rate of heat transfer higher? How does the convection heat transfer coefficient differ from the thermal conductivity of a fluid? g) Define incompressible flow and incompressible fluid. Must the flow of a compressible fluid necessarily be treated as compressible? un r. Luma

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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