(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 41°C. if the power radiated by sphere is 87 W, calculate its emissivity value? (1c).If the same sphere is enclosed in room whose walls are kept at -15°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 41°C. if the power radiated by sphere is 87 W, calculate its emissivity value? (1c).If the same sphere is enclosed in room whose walls are kept at -15°C, what is the net flow rate of energy out of the sphere in Watts (W)

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter13: Temperature, Kinetic Theory, And The Gas Laws

Section: Chapter Questions

Problem 18PE: Most automobiles have a coolant reservoir to catch radiator fluid than may overflow when 1he engine...

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