Assume a steel ball has just been manufactured with a diameter of 10 cm and has a temperature of 877°C. The ball is cooling in air with an ambient temperature of 25°C and a convection coefficient of 20 W/m².°C. The thermal conductivity, density, and specific heat of steel are, respectively, 40 W/m.°C, 7800 kg/m³, and 450 J/kg.°c. Find the time it will take for the steel ball to reach a temperature of 35°C in the center? Neglect radiation. 13002 A C.

Assume a steel ball has just been manufactured with a diameter of 10 cm and has a temperature of 877°C. The ball is cooling in air with an ambient temperature of 25°C and a convection coefficient of 20 W/m².°C. The thermal conductivity, density, and specific heat of steel are, respectively, 40 W/m.°C, 7800 kg/m³, and 450 J/kg.°c. Find the time it will take for the steel ball to reach a temperature of 35°C in the center? Neglect radiation. 13002 A C.

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 2.25P: Show that the rate of heat conduction per unit length through a long, hollow cylinder of inner...

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