Question 1

Molecules in a liquid

Accepted Answer

A)  have little influence on one another. 
B)  have little influence on one another except during their frequent but brief collisions. 
C)  are close together and exert forces on one another that are comparable to the forces that bind atoms into molecules. 
D)  form temporary short-range bonds that continually break and re-form due to the thermal kinetic energy of the molecules. 
E)  are always arranged in a crystalline structure. 
A)  have little influence on one another. 
B)  have little influence on one another except during their frequent but brief collisions. 
C)  are close together and exert forces on one another that are comparable to the forces that bind atoms into molecules. 
D)  form temporary short-range bonds that continually break and re-form due to the thermal kinetic energy of the molecules. 
E)  are always arranged in a crystalline structure.

Question 2

The classical free-electron theory of metals is inadequate in that it

Accepted Answer

A)  assumes the average energy of the electrons to be 3kT/2. 
B)  assumes the energy distribution to be a Maxwell-Boltzmann distribution. 
C)  fails to incorporate the exclusion principle. 
D)  assumes the applicability of the equipartition theorem. 
E)  incorporates all of these. 
A)  assumes the average energy of the electrons to be 3kT/2. 
B)  assumes the energy distribution to be a Maxwell-Boltzmann distribution. 
C)  fails to incorporate the exclusion principle. 
D)  assumes the applicability of the equipartition theorem. 
E)  incorporates all of these.

Question 3

The symbol for an npn transistor is

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 4

The effect known as avalanche breakdown occurs at point

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 5

If you increase the temperature of a semiconductor, you can expect to measure

Accepted Answer

A)  no change in its resistance. 
B)  an increase in its resistance. 
C)  an increase in the potential difference across it. 
D)  a decrease in the potential difference across it. 
E)  no change in the potential difference across it. 
A)  no change in its resistance. 
B)  an increase in its resistance. 
C)  an increase in the potential difference across it. 
D)  a decrease in the potential difference across it. 
E)  no change in the potential difference across it.

Question 6

The equilibrium spacing r0 for NaCl is 0.282 nm and the mass of 1 mol of NaCl is
58)4 g. The density of NaCl must be

Accepted Answer

A)  10.2 g/cm3  
B)  6.35 g/cm3  
C)  3.68 g/cm3  
D)  2.16 g/cm3  
E)  1.08 g/cm3  
A)  10.2 g/cm3  
B)  6.35 g/cm3  
C)  3.68 g/cm3  
D)  2.16 g/cm3  
E)  1.08 g/cm3

Question 7

Metallic compounds have been found to exhibit superconductivity at temperatures as high as

Accepted Answer

A)  273 K 
B)  164 K 
C)  176 K 
D)  188 K 
E)  243 K 
A)  273 K 
B)  164 K 
C)  176 K 
D)  188 K 
E)  243 K

Question 8

If you want to produce a crystal from a liquid, you

Accepted Answer

A)  cool the liquid slowly so that the molecules gradually lose their kinetic energy and thus form a large number of stable bonds. 
B)  cool the liquid rapidly to remove its internal energy before the molecules have a chance to form many bonds. 
C)  maintain the temperature of the liquid while increasing the pressure applied to the liquid. 
D)  maintain the temperature of the liquid while decreasing the pressure applied to the liquid. 
E)  warm the liquid while decreasing its pressure. 
A)  cool the liquid slowly so that the molecules gradually lose their kinetic energy and thus form a large number of stable bonds. 
B)  cool the liquid rapidly to remove its internal energy before the molecules have a chance to form many bonds. 
C)  maintain the temperature of the liquid while increasing the pressure applied to the liquid. 
D)  maintain the temperature of the liquid while decreasing the pressure applied to the liquid. 
E)  warm the liquid while decreasing its pressure.

Question 9

Use the following to answer the next question.
 
-At what energy is the Fermi factor equal to 0.2 for copper at T = 300 K?

Accepted Answer

A)  7.08 eV 
B)  7.00 eV 
C)  7.06 eV 
D)  7.02 eV 
E)  7.18 eV 
A)  7.08 eV 
B)  7.00 eV 
C)  7.06 eV 
D)  7.02 eV 
E)  7.18 eV

Question 10

A semiconductor for which it is true that the major charge carriers are electrons

Accepted Answer

A)  is called an n-type semiconductor. 
B)  is called a p-type semiconductor. 
C)  accepts positive charges from filled valence bands. 
D)  is devoid of acceptor levels. 
E)  None of these is correct. 
A)  is called an n-type semiconductor. 
B)  is called a p-type semiconductor. 
C)  accepts positive charges from filled valence bands. 
D)  is devoid of acceptor levels. 
E)  None of these is correct.

Question 11

If you want to produce an amorphous solid from a liquid, you

Accepted Answer

A)  cool the liquid slowly so that the molecules gradually lose their kinetic energy and thus form a maximum number of bonds. 
B)  cool the liquid rapidly to remove its internal energy before the molecules have a chance to form many bonds. 
C)  maintain the temperature of the liquid while increasing the pressure applied to the liquid. 
D)  maintain the temperature of the liquid while decreasing the pressure applied to the liquid. 
E)  warm the liquid while decreasing its pressure. 
A)  cool the liquid slowly so that the molecules gradually lose their kinetic energy and thus form a maximum number of bonds. 
B)  cool the liquid rapidly to remove its internal energy before the molecules have a chance to form many bonds. 
C)  maintain the temperature of the liquid while increasing the pressure applied to the liquid. 
D)  maintain the temperature of the liquid while decreasing the pressure applied to the liquid. 
E)  warm the liquid while decreasing its pressure.

Question 12

An alternating-current generator is producing a voltage with a frequency of 60 Hz. In the diagram, D is a solid-state diode made from a pn germanium junction. Which graph best describes the current I through the resistor R as a function of time?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  None of these is correct. 
A)  1 
B)  2 
C)  3 
D)  4 
E)  None of these is correct.

Question 13

Insulated electrical wires often have a maximum voltage rating, i.e., the insulation on the wire is safe up to the rated voltage. The reason why the insulator is not safe at higher voltage is because

Accepted Answer

A)  there is a possibility of electric breakdown, which will cause electrons in the valence band of the insulator to be promoted to the conduction band making the insulator a conductor. 
B)  the wire will then carry more current, making the wire unsafe. 
C)  most households only have 240 V maximum so there is no point having a higher voltage rating. 
D)  it is the manufacturer's way of preventing users from transmitting higher voltage. 
E)  None of these is correct. 
A)  there is a possibility of electric breakdown, which will cause electrons in the valence band of the insulator to be promoted to the conduction band making the insulator a conductor. 
B)  the wire will then carry more current, making the wire unsafe. 
C)  most households only have 240 V maximum so there is no point having a higher voltage rating. 
D)  it is the manufacturer's way of preventing users from transmitting higher voltage. 
E)  None of these is correct.

Question 14

Use the following to answer the next question.  
-The graph that represents the density of states g(E) in a Fermi gas is

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 15

Which of the following statements is false?

Accepted Answer

A)  The probability of an energy state being occupied is called the Fermi factor. 
B)  At temperatures greater than T = 0, some electrons occupy higher energy states because of thermal energy gained during collisions with the lattice. 
C)  An electron cannot move to a higher or lower energy state unless it is unoccupied. 
D)  Since the kinetic energy of lattice ions is of the order of kT, electrons cannot gain much more energy than kT in collisions with these ions. 
E)  None of these is false. 
A)  The probability of an energy state being occupied is called the Fermi factor. 
B)  At temperatures greater than T = 0, some electrons occupy higher energy states because of thermal energy gained during collisions with the lattice. 
C)  An electron cannot move to a higher or lower energy state unless it is unoccupied. 
D)  Since the kinetic energy of lattice ions is of the order of kT, electrons cannot gain much more energy than kT in collisions with these ions. 
E)  None of these is false.

Question 16

If you apply a voltage of 3 µV to a Josephson junction, you can expect to measure a frequency of

Accepted Answer

A)  145 MHz 
B)  1450 MHz 
C)  346 kHz 
D)  346 Hz 
E)  527 Mhz 
A)  145 MHz 
B)  1450 MHz 
C)  346 kHz 
D)  346 Hz 
E)  527 Mhz

Question 17

In the classical free-electron theory of metals,

Accepted Answer

A)  a metal is pictured as a regular three-dimensional array of atoms or ions. 
B)  a metal contains a large number of electrons that are free to move throughout the whole metal. 
C)  thermal equilibrium is maintained by collisions of electrons with the lattice ions. 
D)  electrons in the absence of an electric field move about the metal much as gas molecules move in a container. 
E)  All of these are true. 
A)  a metal is pictured as a regular three-dimensional array of atoms or ions. 
B)  a metal contains a large number of electrons that are free to move throughout the whole metal. 
C)  thermal equilibrium is maintained by collisions of electrons with the lattice ions. 
D)  electrons in the absence of an electric field move about the metal much as gas molecules move in a container. 
E)  All of these are true.

Question 18

Which of the following expressions correctly describes the dependence of the resistivity$\rho$ on the electric field E, the number of conduction electrons ne, the electronic charge e, and the electron drift velocity vd?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 19

If the atoms are treated as solid spheres, the fraction of volume occupied by the atoms in a body-centered-cubic unit cell is

Accepted Answer

A)  0.45 
B)  0.52 
C)  0.65  
D)  0.68 
E)  0.74  
A)  0.45 
B)  0.52 
C)  0.65  
D)  0.68 
E)  0.74

Question 20

The resistivity of copper at 20ºC is 1.7 *10-8  $\Omega$ · m and the number of electrons per cubic centimeter is 8.47 * 1022. If you take the average speed of the electrons to be equal to their root-mean-square speed (at T = 300 K) of 1.17 *105 m/s, it follows that their mean free path, $\lambda$, must be

Accepted Answer

A)  1.23 nm 
B)  1.86 nm 
C)  2.35 nm 
D)  2.89 nm 
E)  None of these is correct. 
A)  1.23 nm 
B)  1.86 nm 
C)  2.35 nm 
D)  2.89 nm 
E)  None of these is correct.

Molecules in a liquid

The classical free-electron theory of metals is inadequate in that it

The symbol for an npn transistor is

The effect known as avalanche breakdown occurs at point

If you increase the temperature of a semiconductor, you can expect to measure

The equilibrium spacing r₀ for NaCl is 0.282 nm and the mass of 1 mol of NaCl is 58)4 g. The density of NaCl must be

Metallic compounds have been found to exhibit superconductivity at temperatures as high as

If you want to produce a crystal from a liquid, you

Use the following to answer the next question. -At what energy is the Fermi factor equal to 0.2 for copper at T = 300 K?

A semiconductor for which it is true that the major charge carriers are electrons

If you want to produce an amorphous solid from a liquid, you

An alternating-current generator is producing a voltage with a frequency of 60 Hz. In the diagram, D is a solid-state diode made from a pn germanium junction. Which graph best describes the current I through the resistor R as a function of time?

Insulated electrical wires often have a maximum voltage rating, i.e., the insulation on the wire is safe up to the rated voltage. The reason why the insulator is not safe at higher voltage is because

Use the following to answer the next question. -The graph that represents the density of states g(E) in a Fermi gas is

Which of the following statements is false?

If you apply a voltage of 3 µV to a Josephson junction, you can expect to measure a frequency of

In the classical free-electron theory of metals,

Which of the following expressions correctly describes the dependence of the resistivity $\rho$ on the electric field E, the number of conduction electrons n_e, the electronic charge e, and the electron drift velocity v_d?

If the atoms are treated as solid spheres, the fraction of volume occupied by the atoms in a body-centered-cubic unit cell is

The Electric Field I: Discrete Charge Distributions

The Electric Field II: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Relativity

Nuclear Physics

Elementary Particles and the Beginning of the Universe

Filters

Exam 18: Solids and the Theory of Conduction

Molecules in a liquid

The classical free-electron theory of metals is inadequate in that it

The symbol for an npn transistor is

The effect known as avalanche breakdown occurs at point

If you increase the temperature of a semiconductor, you can expect to measure

The equilibrium spacing r0 for NaCl is 0.282 nm and the mass of 1 mol of NaCl is 58)4 g. The density of NaCl must be

Metallic compounds have been found to exhibit superconductivity at temperatures as high as

If you want to produce a crystal from a liquid, you

Use the following to answer the next question. -At what energy is the Fermi factor equal to 0.2 for copper at T = 300 K?

A semiconductor for which it is true that the major charge carriers are electrons

If you want to produce an amorphous solid from a liquid, you

An alternating-current generator is producing a voltage with a frequency of 60 Hz. In the diagram, D is a solid-state diode made from a pn germanium junction. Which graph best describes the current I through the resistor R as a function of time?

Insulated electrical wires often have a maximum voltage rating, i.e., the insulation on the wire is safe up to the rated voltage. The reason why the insulator is not safe at higher voltage is because

Use the following to answer the next question. -The graph that represents the density of states g(E) in a Fermi gas is

Which of the following statements is false?

If you apply a voltage of 3 µV to a Josephson junction, you can expect to measure a frequency of

In the classical free-electron theory of metals,

Which of the following expressions correctly describes the dependence of the resistivity ρ\rhoρ on the electric field E, the number of conduction electrons ne, the electronic charge e, and the electron drift velocity vd?

If the atoms are treated as solid spheres, the fraction of volume occupied by the atoms in a body-centered-cubic unit cell is

The Electric Field I: Discrete Charge Distributions

The Electric Field II: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Relativity

Nuclear Physics

Elementary Particles and the Beginning of the Universe

Filters

The equilibrium spacing r₀ for NaCl is 0.282 nm and the mass of 1 mol of NaCl is 58)4 g. The density of NaCl must be

Which of the following expressions correctly describes the dependence of the resistivity $\rho$ on the electric field E, the number of conduction electrons n_e, the electronic charge e, and the electron drift velocity v_d?