University Physics Volume 3
17th Edition
ISBN: 9781938168185
Author: William Moebs, Jeff Sanny
Publisher: OpenStax
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Textbook Question
Chapter 9, Problem 16CQ
Why does the horizontal Line in the graph in Figure 9.12 suddenly stop at the Fermi energy?
Figure 9.12 (a) Density of state for a free electron gas; (b) probability that a state is occupied at T = 0 K; (c) density if occupied states at T = 0 k.
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Suppose we have an ideal fermion gas of identical particles in a "box" at T = 0 K.
Which of the following statements are true?
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The multiplicity of the gas is =1
b.
The multiplicity of the gas is =N!
C.
If the gas consists of electrons with densities that correspond to the typical densities
of conduction electrons in metals, only a part of the electrons can contribute to the
heat capacity of the system as the temperature rises.
d.
If the gas consists of electrons with densities corresponding the typical densities
of conduction electrons in metals, all electrons can easily contribute to the heat
capacity of the system as the temperature rises.
Q10: Find the accurate probability for an electron to occupy a level 0.2eV
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Chapter 9 Solutions
University Physics Volume 3
Ch. 9 - Check Your Understanding Why is the potential...Ch. 9 - Check Your Understanding What does the energy...Ch. 9 - Check Your Understanding If the dissociation...Ch. 9 - Check Your Understanding What happens to the...Ch. 9 - Check Your Understanding How does the magnitude of...Ch. 9 - Check Your Understanding What conditions are...Ch. 9 - What is the main difference between an ionic bond,...Ch. 9 - For the following cases, what type of bonding...Ch. 9 - Describe three steps to ionic bonding.Ch. 9 - What prevents a positive and negative ion from...
Ch. 9 - For the H2 molecule, why must the spins the...Ch. 9 - Does the absorption spectrum of the diatomic...Ch. 9 - Rank the energy spacing (E) of the following...Ch. 9 - Explain key features of a vibrational-rotation...Ch. 9 - Why is tbe equilibrium separation distance between...Ch. 9 - Describe the difference between a face-centered...Ch. 9 - In sodium chloride, how many Clatoms are “nearest...Ch. 9 - In cesium iodide, how many Clatoms are "nearest...Ch. 9 - The NaCl crystal structure is FCC. 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The equilibrium...Ch. 9 - The potential energy of a crystal is - 8.10 eV/ion...Ch. 9 - The measured density of a NaF crystal is 2.558...Ch. 9 - What value of the repulsion constant, n, gives the...Ch. 9 - Determine the dissociation energy of 12 moles of...Ch. 9 - The measured density of a KCl crystal is 1.984...Ch. 9 - What value of the repulsion constant, n, gives the...Ch. 9 - The measured density of a CsCl crystal is 3.988...Ch. 9 - What is the difference in energy between the...Ch. 9 - An electron is confined to a metal cube of I = 0.8...Ch. 9 - What value of energy corresponds to a density of...Ch. 9 - Compare the density of states at 2.5 eV and 0.25...Ch. 9 - Consider a cube of copper with edges 1.50 mm long....Ch. 9 - If there is one free electron per atom of copper,...Ch. 9 - Determine the Fermi energy and temperature for...Ch. 9 - For a one-dimensional crystal, write the lattice...Ch. 9 - What is the main difference between an insulator...Ch. 9 - What is the longest wavelength for a photon that...Ch. 9 - A valence electron in a crystal absorbs a photon...Ch. 9 - An experiment is performed to demonstrate the Hall...Ch. 9 - Suppose that the cross-sectional area of the strip...Ch. 9 - A current-carrying copper wire with cross-section...Ch. 9 - The Hall effect is demonstrated in the laboratory....Ch. 9 - Show that for V less than zero, InetI0.Ch. 9 - A p-n diode has a reverse saturation current...Ch. 9 - The collector current of a transistor is 3.4 A for...Ch. 9 - Applying the positive end of a battery to the...Ch. 9 - The base current of a transistor is 4.4 A, and its...Ch. 9 - At what temperature, in terms of Tc, is the...Ch. 9 - What is the critical magnetic field for lead at T...Ch. 9 - A Pb wire wound in a tight solenoid of diameter of...Ch. 9 - A tightly wound solenoid at 4.0 K is 50 cm long...Ch. 9 - Potassium fluoride (KF) is a molecule formed by...Ch. 9 - For the preceding problem, sketch the potential...Ch. 9 - The separation between hydrogen atoms in a H2...Ch. 9 - The characteristic energy of the Cl2 molecule is...Ch. 9 - Determine the lowest three rotational energy...Ch. 9 - A carbon atom can hybridize in the...Ch. 9 - List five main characteristics of ionic crystals...Ch. 9 - Why is bonding in favorable? 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