7 Q.3:Consider photons contained in a three-dimensional cavity of unit volume. The density ofstates for the photons is given byD(E)dEdɛ%3!a) Show that the number of thermally excited photons is given by the expressionV(k,T)N =2.404-b) Suppose that the number of photons N in the universe is constant, at a concentration of 1026 m.Find the critical Te such that Ne=N.Note: You are given thatdx = 2.404e -1

Density of states function is given by,D(E)dE=Vh3c3E2π2dE=CE2dE where C=Vh3c3π2

Q.3:Consider photons contained in a three-dimensional cavity of unit volume. The density of states for the photons is given by D(E)dƐ : %3D a) Show that the number of thermally excited photons is given by the expression N =2.404 (k,T)' %3D b) Suppose that the number of photons N in the universe is constant, at a concentration of 1026 m³. Find the critical Te such that Nex=N. x dx = 2.404 e-1 Note: You are given that %3D

Q.3:Consider photons contained in a three-dimensional cavity of unit volume. The density of states for the photons is given by D(E)dƐ : %3D a) Show that the number of thermally excited photons is given by the expression N =2.404 (k,T)' %3D b) Suppose that the number of photons N in the universe is constant, at a concentration of 1026 m³. Find the critical Te such that Nex=N. x dx = 2.404 e-1 Note: You are given that %3D

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter7: Tunneling Phenomena

Section: Chapter Questions

Problem 16P

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