Essential University Physics (3rd Edition)
3rd Edition
ISBN: 9780134202709
Author: Richard Wolfson
Publisher: PEARSON
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Chapter 34, Problem 72P
To determine
To show that Plank’s law reduces Rayleigh-jeans law.
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In a photoelectric experiment it is found that a stopping potential of 1.00 V is needed to stop all the electrons when incident light of wavelength 225 nm is used and 1.5 V is needed for light of
wavelength 207 nm.
From these data determine Planck's constant. (Enter your answer, in eV s, to at least four significant figures.)
4.2367e-15 X ev s
From these data determine the work function (in eV) of the metal.
4.6
X ev
For the thermal radiation from an ideal blackbody radiator with a surface temperature of 2000 K, let Ic represent the intensity per unit wavelength according to the classical expression for the spectral radiancy and IP represent the corresponding intensity per unit wavelength according to the Planck expression.What is the ratio Ic/IP for a wavelength of (a) 400 nm (at the blue end of the visible spectrum) and (b) 200 mm (in the far infrared)? (c) Does the classical expression agree with the Planck expression in the shorter wavelength range or the longer wavelength range?
In a particular photoelectric experiment, a stopping potential of 2.1 V is measured when
ultraviolet light with a wavelength of 290 nm is incident on a metal. Given the light of speed
c = 3.0 x 108 m/s and Planck constant h = 6.625 x 10-34 J. s or 4.14 × 10-15 eV.s
%3D
(a) Describe and illustrate the photoelectric experiment and explain why it cannot be
explained by classical physics.
(b) Using the same setup and metal, determine the stopping potential if blue light with a
wavelength of 440 nm is used, instead of the ultraviolet light.
(c) Using the same setup and metal, describe what happened if a red light with a wavelength
of 620 nm is used, instead of the ultraviolet light.
Chapter 34 Solutions
Essential University Physics (3rd Edition)
Ch. 34.2 - Prob. 34.1GICh. 34.3 - If you replot Fig. 34.7 for a material with a...Ch. 34.3 - Prob. 34.3GICh. 34.4 - Prob. 34.4GICh. 34.5 - Prob. 34.5GICh. 34.6 - Prob. 34.6GICh. 34 - Prob. 1FTDCh. 34 - Prob. 2FTDCh. 34 - Prob. 3FTDCh. 34 - Prob. 4FTD
Ch. 34 - Prob. 5FTDCh. 34 - Prob. 6FTDCh. 34 - Prob. 7FTDCh. 34 - Prob. 8FTDCh. 34 - Prob. 9FTDCh. 34 - Prob. 10FTDCh. 34 - Prob. 11FTDCh. 34 - Prob. 12FTDCh. 34 - Prob. 13FTDCh. 34 - Prob. 14FTDCh. 34 - Prob. 15ECh. 34 - The surface temperature of the star Rigel is 104K....Ch. 34 - Prob. 17ECh. 34 - Prob. 18ECh. 34 - Prob. 19ECh. 34 - Prob. 20ECh. 34 - Prob. 21ECh. 34 - Prob. 22ECh. 34 - Prob. 23ECh. 34 - Prob. 24ECh. 34 - Prob. 25ECh. 34 - Prob. 26ECh. 34 - Prob. 27ECh. 34 - Prob. 28ECh. 34 - Prob. 29ECh. 34 - Prob. 30ECh. 34 - Prob. 31ECh. 34 - Prob. 32ECh. 34 - Prob. 33ECh. 34 - Prob. 34ECh. 34 - Prob. 35ECh. 34 - Prob. 36ECh. 34 - Prob. 37ECh. 34 - Prob. 38PCh. 34 - Prob. 39PCh. 34 - Prob. 40PCh. 34 - Prob. 41PCh. 34 - Prob. 42PCh. 34 - Prob. 43PCh. 34 - Prob. 44PCh. 34 - Prob. 45PCh. 34 - Prob. 46PCh. 34 - Prob. 47PCh. 34 - Prob. 48PCh. 34 - Prob. 49PCh. 34 - Prob. 50PCh. 34 - Prob. 51PCh. 34 - Prob. 52PCh. 34 - Prob. 53PCh. 34 - Prob. 54PCh. 34 - Prob. 55PCh. 34 - Prob. 56PCh. 34 - Prob. 57PCh. 34 - Prob. 58PCh. 34 - Prob. 59PCh. 34 - Prob. 60PCh. 34 - Prob. 61PCh. 34 - Prob. 62PCh. 34 - Prob. 63PCh. 34 - Prob. 64PCh. 34 - Prob. 65PCh. 34 - Prob. 66PCh. 34 - Prob. 67PCh. 34 - Prob. 68PCh. 34 - Prob. 69PCh. 34 - Prob. 70PCh. 34 - Prob. 71PCh. 34 - Prob. 72PCh. 34 - Prob. 73PCh. 34 - Prob. 74PCh. 34 - Prob. 75PCh. 34 - Prob. 76PCh. 34 - Prob. 77PCh. 34 - Prob. 78PCh. 34 - Prob. 79PCh. 34 - Prob. 80PCh. 34 - Prob. 81PCh. 34 - Prob. 82PCh. 34 - Prob. 83PCh. 34 - Prob. 84PPCh. 34 - Prob. 85PPCh. 34 - Prob. 86PPCh. 34 - Prob. 87PP
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