Modern Physics
2nd Edition
ISBN: 9780805303087
Author: Randy Harris
Publisher: Addison Wesley
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Question
Chapter 3, Problem 11E
(a)
To determine
The Planck’s spectral energy density in the limit of small frequencies.
(b)
To determine
The Planck’s spectral energy density at high frequencies.
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Planck's radiation law can be written
ux
=
8лhc 1
25 eßhc/2-1
Show that the wavelength corresponding to the maximum energy density of the
radiation fulfills the condition
λmax T
=
.
constant
What is this constant? (This result is known as Wien's transition law.) Tip: you can
solve the constant approximation by e.g. iterating an equation of the form
Xn = 5 (1-e¯Xn-1)
with a suitable initial value x1.
The wavelength λmax at which the Planck distribution is a maximum can be found by solving dρ(λ,T)/dT = 0. Differentiate ρ(λ,T) with respect to T and show that the condition for the maximum can be expressed as xex − 5(ex − 1) = 0, where x = hc/λkT. There are no analytical solutions to this equation, but a numerical approach gives x = 4.965 as a solution. Use this result to confirm Wien’s law, that λmaxT is a constant, deduce an expression for the constant, and compare it to the value quoted in the text.
please solve asap
Chapter 3 Solutions
Modern Physics
Ch. 3 - Prob. 1CQCh. 3 - Prob. 2CQCh. 3 - Prob. 3CQCh. 3 - Prob. 4CQCh. 3 - Prob. 5CQCh. 3 - Prob. 6CQCh. 3 - Prob. 7CQCh. 3 - A ball rebounds elastically from the floor. What...Ch. 3 - Prob. 9CQCh. 3 - Prob. 10CQ
Ch. 3 - Prob. 11ECh. 3 - Prob. 12ECh. 3 - Prob. 13ECh. 3 - Prob. 14ECh. 3 - Prob. 15ECh. 3 - Prob. 16ECh. 3 - Prob. 17ECh. 3 - What is the stopping potential when 250 nm...Ch. 3 - Prob. 19ECh. 3 - Prob. 20ECh. 3 - Prob. 21ECh. 3 - Prob. 22ECh. 3 - Prob. 23ECh. 3 - Prob. 24ECh. 3 - Prob. 25ECh. 3 - Prob. 26ECh. 3 - Prob. 27ECh. 3 - Prob. 28ECh. 3 - Prob. 29ECh. 3 - Prob. 30ECh. 3 - Prob. 31ECh. 3 - Prob. 32ECh. 3 - Prob. 33ECh. 3 - Prob. 34ECh. 3 - Prob. 35ECh. 3 - Prob. 36ECh. 3 - Verify that the Chapter 2 formula KE=mc2 applies...Ch. 3 - Prob. 38ECh. 3 - Prob. 39ECh. 3 - Prob. 40ECh. 3 - Prob. 41ECh. 3 - Prob. 42ECh. 3 - Prob. 43ECh. 3 - Prob. 44ECh. 3 - Prob. 45ECh. 3 - Prob. 46ECh. 3 - Prob. 47CECh. 3 - Prob. 49CECh. 3 - Prob. 50CECh. 3 - Prob. 51CECh. 3 - Prob. 52CECh. 3 - Prob. 53CECh. 3 - Prob. 54CECh. 3 - Prob. 55CE
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