Modern Physics
2nd Edition
ISBN: 9780805303087
Author: Randy Harris
Publisher: Addison Wesley
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Question
Chapter 6, Problem 12CQ
To determine
Whether the group velocity exceed the phase velocity or not; the effective mass is same for almost same or different wave numbers.
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Students have asked these similar questions
The greenhouse-gas carbon dioxide molecule CO2
strongly absorbs infrared radiation when its vibrational
normal modes are excited by light at the normal-mode
frequencies. CO₂ is a linear triatomic molecule, as
shown in (Figure 1), with oxygen atoms of mass mo
bonded to a central carbon atom of mass mc. You
know from chemistry that the atomic masses of carbon
and oxygen are, respectively, 12 and 16. Assume that
the bond is an ideal spring with spring constant k.
There are two normal modes of this system for which
oscillations take place along the axis. (You can ignore
additional bending modes.) In this problem, you will find
the normal modes and then use experimental data to
determine the bond spring constant.
Figure
O
1
mo
1x₁
2
mc
1 of 1
3
mo
1Xz
Part A
Let x₁, x2, and 3 be the atoms' positions measured from their equilibrium positions. First, use Hooke's law to write the net force
on each atom. Pay close attention to signs! For each oxygen, the net force equals mod²x/dt². Carbon has a…
The greenhouse-gas carbon dioxide molecule CO2
strongly absorbs infrared radiation when its vibrational
normal modes are excited by light at the normal-mode
frequencies. CO₂ is a linear triatomic molecule, as
shown in (Figure 1), with oxygen atoms of mass mo
bonded to a central carbon atom of mass mc. You
know from chemistry that the atomic masses of carbon
and oxygen are, respectively, 12 and 16. Assume that
the bond is an ideal spring with spring constant k
There are two normal modes of this system for which
oscillations take place along the axis. (You can ignore
additional bending modes.) In this problem, you will find
the normal modes and then use experimental data to
determine the bond spring constant.
Figure
O
1
mo
T
X₁
k
C
2
mc
1X₂
k
1 of 1 >
O
3
mo
1 X3
Part A
Let ₁, 2, and 3 be the atoms' positions measured from their equilibrium positions. First, use Hooke's law to write the net force
on each atom. Pay close attention to signs! For each oxygen, the net force equals mod²x/dt².…
1.7 A crystal has a basis of one atom per lattice point and a set of primitive translation
vectors (in A):
c = 1.5(i + j+ k),
a = 3i,
where i, j and k are unit vectors in the x, y and z directions of a Cartesian coordinate
system. What is the Bravais lattice type of this crystal, and what are the Miller indices
of the set of planes most densely populated with atoms? Calculate the volumes of the
primitive unit cell and the conventional unit cell.
b= 3j.
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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