A long copper rod of diameter 2.0 cm is initially at a uniform temperature of 100°C. It is now exposed to 'an air stream at 13°C with a heat transfer coefficient of 200 W/m2.K. How long would it take for the copper road to cool to an average temperature of 25°C? (Express the answers in seconds.) (Thermal properties of copper: k= 401 W/m-°C, p= 8933 kg/m3, Cp = 0.385 kJ/kg.°C.) 0.17 x S.

A long copper rod of diameter 2.0 cm is initially at a uniform temperature of 100°C. It is now exposed to 'an air stream at 13°C with a heat transfer coefficient of 200 W/m2.K. How long would it take for the copper road to cool to an average temperature of 25°C? (Express the answers in seconds.) (Thermal properties of copper: k= 401 W/m-°C, p= 8933 kg/m3, Cp = 0.385 kJ/kg.°C.) 0.17 x 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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

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