Heat And Mass Transfer
5th Edition
ISBN: 9781259173301
Author: Çengel, Yunus A., Ghajar, Afshin J. (afshin Jahanshahi)
Publisher: Mcgraw Hill Education,
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Textbook Question
Chapter 1, Problem 158P
Over 90 percent of the energy dissipated by an incandescent lightbulb is in the form of heat, not light. What is the temperature of a vacuum-enclosed tungsten filament with an exposed surface area of 2.03 cm2 in a 100-W incandescent lightbulb? The emissivity of tungsten at eh anticipated high temperatures is about 0.35. Note that the lightbulb consumes 100 W of electrical energy and dissipates all of it by radiation.
- 1870 K
- 2230 K
- 2640 K
- 3120 K
- 2980 K
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Chapter 1 Solutions
Heat And Mass Transfer
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