(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 250 mm radius is at a temperature of 37°C. If the power radiated by sphere is 87 W, calculate its emissivity value? (1c).lf the same sphere is enclosed in room whose walls are kept at -9°C, what is the net flow rate of energy out of the sphere in Watts (W)

(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 250 mm radius is at a temperature of 37°C. If the power radiated by sphere is 87 W, calculate its emissivity value? (1c).lf the same sphere is enclosed in room whose walls are kept at -9°C, what is the net flow rate of energy out of the sphere in Watts (W)

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 36CQ: Satellites designed to observe the radiation from cold (3 K) dark space have sensors that are shaded...

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