An irregularly shaped solid made of a material with a density of 3200 kg/m³ has a volume of 0.003 m3 and a surface area of 0.07 m². The thermal conductivity of the material is 300 W/m K, and its specific heat is 500 J/kg K. Initially, there is a 100°C difference between the solid and its environment, what is the approximate time it will take for this system to have the difference between its temperature and the environment to be one-third of the initial difference? Use h- 60 W/m-K for the environment. Express your answer in minutes.

An irregularly shaped solid made of a material with a density of 3200 kg/m³ has a volume of 0.003 m3 and a surface area of 0.07 m². The thermal conductivity of the material is 300 W/m K, and its specific heat is 500 J/kg K. Initially, there is a 100°C difference between the solid and its environment, what is the approximate time it will take for this system to have the difference between its temperature and the environment to be one-third of the initial difference? Use h- 60 W/m-K for the environment. Express your answer in minutes.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.1P: A plane wall, 7.5 cm thick, generates heat internally at the rate of 105 W/m3. One side of the wall...

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A plane wall 15 cm thick has a thermal conductivity given by the relation k=2.0+0.0005T[W/mK] where T is in kelvin. If one surface of this wall is maintained at 150C and the other at 50C, determine the rate of heat transfer per square meter. Sketch the temperature distribution through the wall.
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