(1a). Black body has emissivity value of 1, but in reality, the emissivity of real objects is less than 1. Why??(1b). The tungsten sphere of 220 mm radius is at a temperature of 43°C. If the power radiated by sphere is 105 W. calculate itsemissivity value?(1c).lf the same sphere is enclosed in room whose walls are kept at -13°C, what is the net flow rate of energy out of the sphere inWatts (W)

1 a) answer- Emissivity is the ratio of the amount of radiation emitted by the surface of the body…

Answered: (1a). Black body has emissivity value…

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(1a). Black body has emissivity value of 1, but in reality, the emissivity of real objects is less than 1. Why??

University Physics Volume 2

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Chapter1: Temperature And Heat

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Problem 49P: The height of the Washington Monument is measured to be 170.00 m on a day when the temperature is...

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Question

(1a). Black body has emissivity value of 1, but in reality, the emissivity of real objects is less than 1. Why??
(1b). The tungsten sphere of 220 mm radius is at a temperature of 43°C. If the power radiated by sphere is 105 W. calculate its
emissivity value?
(1c).lf the same sphere is enclosed in room whose walls are kept at -13°C, what is the net flow rate of energy out of the sphere in
Watts (W)

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