Modern Physics
2nd Edition
ISBN: 9780805303087
Author: Randy Harris
Publisher: Addison Wesley
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Question
Chapter 6, Problem 47E
(a)
To determine
To calculate:
The phase and group velocities.
(b)
To determine
Spread of the wave as it travels.
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The phase velocity v of gravity waves in a liquid of depth h is given by the
formula
v = tanh kh,
k
where g is the acceleration of free fall and k = 2w/2 is the wavenumber, a
being the wavelength. Sketch the dispersion relation for such waves, and
show that the group velocity is always between v2 and v.
Find the phase and group velocities for gravity waves of frequency 1 Hz
in a liquid of depth 0.1 m.
A real wave function is defined on the half-axis:
[0≤x≤00) as y(x) = A(x/xo)e-x/xo
where xo is a given constant with the dimension of length.
a) Plot this function in the dimensionless variables and find the constant A.
b) Present the normalized wave function in the dimensional variables.
Hint: introduce the dimensionless variables = x/xo and Y(5) = Y(5)/A.
Q.18. Verify the statement in the text that, if the phase velocity is the same for all
wavelengths of a certain wave phenomenon (that is, there is no dispersion), the group and
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Chapter 6 Solutions
Modern Physics
Ch. 6 - Prob. 1CQCh. 6 - Prob. 2CQCh. 6 - Prob. 3CQCh. 6 - Prob. 4CQCh. 6 - Prob. 5CQCh. 6 - Prob. 6CQCh. 6 - Prob. 7CQCh. 6 - Prob. 8CQCh. 6 - Prob. 9CQCh. 6 - Prob. 10CQ
Ch. 6 - The diagram below plots (k) versus wave number for...Ch. 6 - Prob. 12CQCh. 6 - Prob. 13ECh. 6 - Prob. 14ECh. 6 - Prob. 15ECh. 6 - Prob. 16ECh. 6 - Prob. 17ECh. 6 - Prob. 18ECh. 6 - Prob. 19ECh. 6 - Prob. 20ECh. 6 - Prob. 21ECh. 6 - Prob. 22ECh. 6 - Prob. 23ECh. 6 - Prob. 24ECh. 6 - Prob. 25ECh. 6 - Prob. 26ECh. 6 - Prob. 27ECh. 6 - Prob. 28ECh. 6 - Obtain the smoothness conditions at the...Ch. 6 - Prob. 30ECh. 6 - Prob. 31ECh. 6 - Jump to Jupiter The gravitational potential energy...Ch. 6 - Prob. 33ECh. 6 - Obtain equation (618) from (616) and (617).Ch. 6 - Prob. 35ECh. 6 - Prob. 36ECh. 6 - Prob. 37ECh. 6 - Prob. 38ECh. 6 - Prob. 39ECh. 6 - Prob. 40ECh. 6 - Prob. 41ECh. 6 - Prob. 42ECh. 6 - Prob. 43ECh. 6 - Prob. 44ECh. 6 - Prob. 45ECh. 6 - Prob. 46ECh. 6 - Prob. 47ECh. 6 - Prob. 48ECh. 6 - Prob. 49ECh. 6 - Prob. 50ECh. 6 - Prob. 51CECh. 6 - Prob. 52CECh. 6 - Prob. 53CECh. 6 - Prob. 54CECh. 6 - Prob. 56CE
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