16-67E A 2-in-diameter spherical ball whose surface ismaintained at a temperature of 170°F is suspended in the middleof a room at 70°F. If the convection heat transfer coefficient is15 Btu/h-ft².°F and the emissivity of the surface is 0.8, deter-mine the total rate of heat transfer from the ball.16-68 An 800-W iron is left on the iron board with itsbase exposed to the air at 20°C. The convection heat trans-fer coefficient between the base surface and the surround-ing air is 35 W/m².K. If the base has an emissivity of0.6 and a surface area of 0.02 m², determine the temperatureof the base of the iron. Answer: 601°CIron800 WFIGURE P16-6820°C

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16-67E A 2-in-diameter spherical ball whose surface is maintained at a temperature of 170°F is suspended in the middle of a room at 70°F. If the convection heat transfer coefficient is 15 Btu/h ft².°F and the emissivity of the surface is 0.8, deter- mine the total rate of heat transfer from the ball.

16-67E A 2-in-diameter spherical ball whose surface is maintained at a temperature of 170°F is suspended in the middle of a room at 70°F. If the convection heat transfer coefficient is 15 Btu/h ft².°F and the emissivity of the surface is 0.8, deter- mine the total rate of heat transfer from the ball.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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