You have a steel ball bearing with a diameter of 1.50 cm (k=40.0 W/(m-K); Density = 7800.0 kg/m^3; and specific heat = 600.0 J/(kg-K)). The ball bearing is initially at a uniform temperature of 1100 K and is then suddenly exposed to convection with a convection temperature of 320.0K and a convection coefficient of 25.0 W/(m2-K). Calculate the following: a) Calculate the time required to cool this ball bearing down to a temperature of 410.0 K. b) Calculate the amount of heat removed from the ball bearing during this cooling process.

You have a steel ball bearing with a diameter of 1.50 cm (k=40.0 W/(m-K); Density = 7800.0 kg/m^3; and specific heat = 600.0 J/(kg-K)). The ball bearing is initially at a uniform temperature of 1100 K and is then suddenly exposed to convection with a convection temperature of 320.0K and a convection coefficient of 25.0 W/(m2-K). Calculate the following: a) Calculate the time required to cool this ball bearing down to a temperature of 410.0 K. b) Calculate the amount of heat removed from the ball bearing during this cooling process.

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 6.4P: An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a...

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