1. Consider a spaceship that has a volume V = 3000 m³, is effectively spherical in shape and has a density comparable to water (p = 1000 kg m-3). It absorbs CMB radiation (TcmB = 2.73K) and radiates its own radiation with a blackbody spectrum of T = 300K. What is its mass, radius and surface area? At what rate does it absorb energy from the CMB? (Hint: You can use the Stefan-Boltzmann law.) How many CMB photons are absorbed per а. b. C. second? d. At what rate does it emit energy through blackbody radiation? What is the net rate that the spaceship temperature would change if the spaceship has an е. effective heat capacity of pure water: C = 4200 J kg-'K-1 ?

1. Consider a spaceship that has a volume V = 3000 m³, is effectively spherical in shape and has a density comparable to water (p = 1000 kg m-3). It absorbs CMB radiation (TcmB = 2.73K) and radiates its own radiation with a blackbody spectrum of T = 300K. What is its mass, radius and surface area? At what rate does it absorb energy from the CMB? (Hint: You can use the Stefan-Boltzmann law.) How many CMB photons are absorbed per а. b. C. second? d. At what rate does it emit energy through blackbody radiation? What is the net rate that the spaceship temperature would change if the spaceship has an е. effective heat capacity of pure water: C = 4200 J kg-'K-1 ?

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 11.66P

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