The emissivity of iron is approximately 0.25. If an iron cube (with a side length of 0.5 m) is heated to 200• C and is placed into a –10.C chamber then answer the following a) What is the net rate of heat loss due to radiation from the iron cube? b) If the cube is placed onto a 0.1 m thick aluminum sheet, and the ground of the chamber is assumed to be held at –10•C, how long will it take in seconds for the cube to lose 1000 J of heat via conduction to the ground? (Note: the thermal conductivity of aluminum is 240 W/(m K)).

The emissivity of iron is approximately 0.25. If an iron cube (with a side length of 0.5 m) is heated to 200• C and is placed into a –10.C chamber then answer the following a) What is the net rate of heat loss due to radiation from the iron cube? b) If the cube is placed onto a 0.1 m thick aluminum sheet, and the ground of the chamber is assumed to be held at –10•C, how long will it take in seconds for the cube to lose 1000 J of heat via conduction to the ground? (Note: the thermal conductivity of aluminum is 240 W/(m K)).

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 1.26P: 1.26 Repeat Problem 1.25 but assume that the surface of the storage vessel has an absorbance (equal...

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