i need the answer quickly (The overall heat transfer coefficient, The critical thickness of insulation and thesteady of heat conduction)Q16) The thermal resistance of one layer plane wall is:A) AX/KaB)ln(n/ro)/2klC) (1/ri -- 1/r.) /4kD) 1 /hAThe thermal resistance of one layer cylinder is:A)AX/KaB)ln(ri /ro)/2klC) (1/ri - 1/ro) /4kD) 1 /hAThe thermal resistance of one layer sphere is:A)AX/KaB)ln(ri /ro)/2klC) (1/ri -- 1/ro) /4kD) 1 /hAThe thermal resistance of heat transfer convection is:A)AX/KaB)ln(ri /ro)/2klC) (1/ri -- 1/ro) 14kD) 1 /hAQ17) The unit of thermal conductivity (k) is:C) m?/secA) w/m cThe unit of thermal diffusivity () is:B) w/m? kC) m2/secA)The unit of heat transfer coefficient by convection (h) is:A)w/m cB) w/m2 kw/m cB) w/m2 kC) m2/secII

(The overall heat transfer coefficient, The critical thickness of insulation and the steady of heat conduction) Q16) The thermal resistance of one layer plane wall is: A) AX/Ka B)ln(r/ro)/2kl C) (1/ri -- 1/r.) 14k D) 1 /hA The thermal resistance of one layer cylinder is: A) AXIKA B)In(ri /ro)/2kl C) (1/ri -- 1/ro) 14k D) 1 /hA The thermal resistance of one layer sphere is: A) B)In(ri /ro)/2kl C)(1/ri -- 1/ro) /4k AX/Ka D) 1 /hA The thermal resistance of heat transfer convection is: B)In(ri /ro)/2kl Q17) The unit of thermal conductivity (k) is: A) AX/Ka C) (1/ri -- 1/ro) /4k D) 1 /hA C) m?/sec A) w/m c The unit of thermal diffusivity () is: A) w/m c The unit of heat transfer coefficient by convection (h) is: A) w/m c B) w/m? k B) w/m2 k C) m2/sec B) w/m2 k C) m2/sec

(The overall heat transfer coefficient, The critical thickness of insulation and the steady of heat conduction) Q16) The thermal resistance of one layer plane wall is: A) AX/Ka B)ln(r/ro)/2kl C) (1/ri -- 1/r.) 14k D) 1 /hA The thermal resistance of one layer cylinder is: A) AXIKA B)In(ri /ro)/2kl C) (1/ri -- 1/ro) 14k D) 1 /hA The thermal resistance of one layer sphere is: A) B)In(ri /ro)/2kl C)(1/ri -- 1/ro) /4k AX/Ka D) 1 /hA The thermal resistance of heat transfer convection is: B)In(ri /ro)/2kl Q17) The unit of thermal conductivity (k) is: A) AX/Ka C) (1/ri -- 1/ro) /4k D) 1 /hA C) m?/sec A) w/m c The unit of thermal diffusivity () is: A) w/m c The unit of heat transfer coefficient by convection (h) is: A) w/m c B) w/m? k B) w/m2 k C) m2/sec B) w/m2 k C) m2/sec

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.20P: A high-speed computer is located in a temperature-controlled room at 26C. When the machine is...

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