Consider a 25-cm-diameter spherical ball at 700 K suspended in air and assume the emissivity of the ball to be ɛ=0.95. Calculate: (i) the total emissive power in kW/m2 (ii) the total amount of radiation emitted by the ball in 3 minutes.

Consider a 25-cm-diameter spherical ball at 700 K suspended in air and assume the emissivity of the ball to be ɛ=0.95. Calculate: (i) the total emissive power in kW/m2 (ii) the total amount of radiation emitted by the ball in 3 minutes.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.26P

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Question

Consider a 25-cm-diameter spherical ball at 700 K suspended
in air and assume the emissivity of the ball to be ɛ=0.95.
Calculate:
(i)
the total emissive power in kW/m_
(ii)
the total amount of radiation emitted by the ball in 3 minutes.

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