Concept explainers
(a)
The power of the emission in the visible region of the spectrum and compare it with ultraviolet and infrared region.
(a)
Answer to Problem 24P
The fraction of the visible power to the ultraviolet and infrared power is
Explanation of Solution
Write the expression for the ratio of intensities from Planck’s law for the different wavelength.
Here,
Conclusion:
Substitute
Substitute
Thus, the fraction of the visible power to the ultraviolet and infrared power is
(b)
The ratio of intensity at
(b)
Explanation of Solution
Write the expression for the Planck’s law of
Here,
Write the expression for the total power radiated by the lamp.
Here,
Write the expression for the fraction of power in the visible region.
Here,
Conclusion:
Substitute
Substitute
Substitute
Thus, the fraction of the visible power to the maximum intensity power is
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Chapter 3 Solutions
Modern Physics for Scientists and Engineers
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