8 mm thick sheets of metal (cp = 750 J/kgK and p = 5250 kg/m³) leave an oven at 1500 K and have the following distribution for spectral, hemispherical emissivity: 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 2 (um) Conduction, convection, and radiation from the surroundings can be neglected. Assume that the only mode of heat transfer is emission to the surroundings at 0 K. 5.2. What is the magnitude of the initial time rate of change of the temperature of the sheet? elect one: O a. 1.0172 K/s O b. 2.3018 K/s O c. 5.9460 K/s O d. 2.872 K/s O e. 3.5695 K/s O f. 7.9053 K/s O g. 10.1481 K/s

8 mm thick sheets of metal (cp = 750 J/kgK and p = 5250 kg/m³) leave an oven at 1500 K and have the following distribution for spectral, hemispherical emissivity: 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 2 (um) Conduction, convection, and radiation from the surroundings can be neglected. Assume that the only mode of heat transfer is emission to the surroundings at 0 K. 5.2. What is the magnitude of the initial time rate of change of the temperature of the sheet? elect one: O a. 1.0172 K/s O b. 2.3018 K/s O c. 5.9460 K/s O d. 2.872 K/s O e. 3.5695 K/s O f. 7.9053 K/s O g. 10.1481 K/s

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 1.30P

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