Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
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Chapter 11, Problem 11.2P
A tungsten filament is heated to 2700 K. At what wavelength is the maximum amount of radiation emitted? What fraction of the total energy is in the visible range
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Chapter 11 Solutions
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Ch. 11 - A tungsten filament is heated to 2700 K. At what...Ch. 11 - Determine the total average hemispherical...Ch. 11 - Prob. 11.4PCh. 11 - Prob. 11.9PCh. 11 -
11.31 A large slab of steel 0.1 m thick contains...Ch. 11 - Prob. 11.32PCh. 11 - 11.41 Determine the steady-state temperatures of...Ch. 11 - Three thin sheets of polished aluminum are placed...Ch. 11 - 11.68 Two infinitely large, black, plane surfaces...
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- Two parallel gray planes that are very large have emissivities of ε1 = 0.8 and ε2 = 0.7; surface 1 is at 1100°F (866.5 K) and surface 2 is at 600°F (588.8 K). Use SI units for the following: (a) What is the net radiation from 1 to 2? (b) If the surfaces are both black, what is the net radiation?arrow_forwardDefine the absorption of radiation incident on an opaque surface of absorptivity α.arrow_forwardDerive the expression for radiation heat exchange between two gray surfaces connected by single refractory surface.arrow_forward
- A body at 1100ºc in a black surrounding at 550ºc has emissivity of 0.4 at 1100ºc and emissivity 0.7 at 550ºc. calculate the rate of heat loss by radiation per unit surface area; i) when the body is assumed to be grey with emissivity 0.4 ii) when the body is not grey. (assume absorptivity is independent of the surface temperature)arrow_forwardThe filament of a 75-W light bulb may be considered a blackbody radiating into a black enclosure at 70°C. The filament diameter is 0.10 mm, and the length is 5 cm. Considering only radiation, determine the filament temperature.arrow_forward2000 degrees * C The temperature of the filament of an incandescent light bulb is . Assuming the filame be a blackbody, determine the fraction of the radiant energy emitted by the filament that falls in visible range. Also, determine the wavelength at which the emission of radiation from the filar peaks.arrow_forward
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