MASTERINGPHYSICS W/ETEXT ACCESS CODE 6
13th Edition
ISBN: 9781269542661
Author: YOUNG
Publisher: PEARSON C
expand_more
expand_more
format_list_bulleted
Question
Chapter 42, Problem 42.55CP
(a)
To determine
To show: When the Fermi energy at absolute zero is
(b)
To determine
Whether the ignoring the relativistic effects is a good approximation for electrons in metals such as copper.
(c)
To determine
The electron concentration within a typical white dwarf star using the assumption that it is made of carbon and all six of the electrons from each carbon atom are able to move freely throughout the star.
(d)
To determine
Whether ignoring the relativistic effects is a good approximation in the structure of a white dwarf star.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
The 2DEG in (iii) is patterned to produce a clean, quasi-1D channel. The current I through
the channel is =
Nev, where N =
the number of electrons, e
the electronic charge and
= the electrons' group velocity. The number of electrons N(ɛ) = f(ɛ, µ)g(ɛ), where
f (ɛ, u) =Fermi-Dirac distribution =
1
and g(ɛ)
density of states = dn/dɛ.
1+exp()
kBT
(a).
Write down the dispersion relation for free electrons of mass m. What is their group
velocity v?
(b).
Find an expression for g(ɛ) involving the group velocity. Leave your answer in terms
of v.
Silicon atoms with a concentration of 7x 1010 cm3 are added to gallium
arsenide GaAs at T = 400 K. Assume that the silicon atoms act as fully ionized dopant atoms and
that 15% of the concentration added replaces gallium atoms to free electrons and 85% replaces
arsenic to create holes. Use the following parameters for GaAs at T = 300 K:
N. = 4.7 x 1017 cm-3 and N, = 7 x 101cm-3. The bandgap is E, = 1.42 eV and it is constant
over the temperature range.
The donor concentration?
An atom’s nucleus is a collection of fermions— protons and neutrons.
(a) In calculating the Fermi energy in a nucleus, the protons and neutrons must be considered separately. Why?
(b) Find the Fermi energy of (i) the protons and (ii) the neutrons in a uranium nucleus, which has a radius of 7.4 x 10-15 m and contains 92 protons and 146 neutrons.
Chapter 42 Solutions
MASTERINGPHYSICS W/ETEXT ACCESS CODE 6
Ch. 42.1 - If electrons obeyed the exclusion principle but...Ch. 42.2 - Prob. 42.2TYUCh. 42.3 - Prob. 42.3TYUCh. 42.4 - One type of thermometer works by measuring the...Ch. 42.5 - Prob. 42.5TYUCh. 42.6 - Prob. 42.6TYUCh. 42.7 - Suppose a negative charge is placed on the gate of...Ch. 42 - Van der Waals bonds occur in many molecules, but...Ch. 42 - Prob. 42.2DQCh. 42 - The H2+ molecule consists of two hydrogen nuclei...
Ch. 42 - The moment of inertia for an axis through the...Ch. 42 - Prob. 42.5DQCh. 42 - Prob. 42.6DQCh. 42 - Prob. 42.7DQCh. 42 - The air you are breathing contains primarily...Ch. 42 - Prob. 42.9DQCh. 42 - Prob. 42.10DQCh. 42 - What factors determine whether a material is a...Ch. 42 - Prob. 42.12DQCh. 42 - Prob. 42.13DQCh. 42 - Prob. 42.14DQCh. 42 - Prob. 42.15DQCh. 42 - Prob. 42.16DQCh. 42 - Prob. 42.17DQCh. 42 - Prob. 42.18DQCh. 42 - Prob. 42.19DQCh. 42 - Prob. 42.20DQCh. 42 - Prob. 42.21DQCh. 42 - Prob. 42.22DQCh. 42 - Prob. 42.23DQCh. 42 - Prob. 42.24DQCh. 42 - If the energy of the H2 covalent bond is 4.48 eV,...Ch. 42 - An Ionic Bond, (a) Calculate the electric...Ch. 42 - Prob. 42.3ECh. 42 - Prob. 42.4ECh. 42 - Prob. 42.5ECh. 42 - Prob. 42.6ECh. 42 - Prob. 42.7ECh. 42 - Two atoms of cesium (Cs) can form a Cs2 molecule....Ch. 42 - Prob. 42.9ECh. 42 - Prob. 42.10ECh. 42 - A lithium atom has mass 1.17 1026 kg, and a...Ch. 42 - Prob. 42.12ECh. 42 - When a hypothetical diatomic molecule having atoms...Ch. 42 - The vibrational and rotational energies of the CO...Ch. 42 - Prob. 42.15ECh. 42 - Prob. 42.16ECh. 42 - Prob. 42.17ECh. 42 - Prob. 42.18ECh. 42 - Prob. 42.19ECh. 42 - Prob. 42.20ECh. 42 - Prob. 42.21ECh. 42 - Prob. 42.22ECh. 42 - Prob. 42.23ECh. 42 - Prob. 42.24ECh. 42 - Prob. 42.25ECh. 42 - Prob. 42.26ECh. 42 - Prob. 42.27ECh. 42 - Prob. 42.28ECh. 42 - Prob. 42.29ECh. 42 - Prob. 42.30ECh. 42 - Prob. 42.31ECh. 42 - Prob. 42.32ECh. 42 - Prob. 42.33PCh. 42 - Prob. 42.34PCh. 42 - Prob. 42.35PCh. 42 - The binding energy of a potassium chloride...Ch. 42 - (a) For the sodium chloride molecule (NaCl)...Ch. 42 - Prob. 42.38PCh. 42 - Prob. 42.39PCh. 42 - Prob. 42.40PCh. 42 - Prob. 42.41PCh. 42 - Prob. 42.42PCh. 42 - Prob. 42.43PCh. 42 - Prob. 42.44PCh. 42 - Prob. 42.45PCh. 42 - Prob. 42.46PCh. 42 - Prob. 42.47PCh. 42 - Prob. 42.48PCh. 42 - Prob. 42.49PCh. 42 - Prob. 42.50PCh. 42 - Prob. 42.51PCh. 42 - Prob. 42.52PCh. 42 - Prob. 42.53CPCh. 42 - Prob. 42.54CPCh. 42 - Prob. 42.55CPCh. 42 - Prob. 42.56PPCh. 42 - Prob. 42.57PPCh. 42 - Prob. 42.58PP
Knowledge Booster
Similar questions
- 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.arrow_forwardSilicon atoms with a concentration of 7x 1010 cm are added to gallium arsenide GaAs at T = 400 K. Assume that the silicon atoms act as fully ionized dopant atoms and that 15% of the concentration added replaces gallium atoms to free electrons and 85% replaces arsenic to create holes. Use the following parameters for GaAs at T = 300 K: N. = 4.7 x 1017cm-3 and N, = 7 x 1018 cm-3. The bandgap is E, = 1.42 eV and it is constant over the temperature range. The intrinsic concentration?arrow_forward1. a) Use the Fermi-Dirac distribution function with no approximations to determine the probability than an energy level at E = EF + 5kT is occupied by an electron. b) Use the Boltzmann approximation to determine the probability than an energy level at E = EF + 5kT is occupied by an electron. c) The % difference between a value R and a reference value Rf is determined by the following equation; % D (R-Rf) x 100% Rf Calculate the % difference between results obtained in a) and b) above using the result without the approximation as the reference value. d) Is the Boltzmann approximation valid when E - EF = 5kT? 1.0 Fermi-Dirac function Boltzmann approximation EF Figure 3.35 | The Fermi-Dirac probability function and the Maxwell-Boltzmann approximation.arrow_forward
- The Fermi energy of sodium is 3.23 eV. (a) Find the average energy Eav of the electrons at absolute zero. (b) What is the speed of an electron that has energy Eav ? (c) At what Kelvin temperature T is kT equal to EF ? (This is called the Fermi temperature for the metal. It is approximately the temperature at which molecules in a classical ideal gas would have the same kinetic energy as the fastest-moving electron in the metal.)arrow_forwardQ2: Assume we have sepration between the conduction band and the Fermi energy as Ec – EF = AE =0.2eV. Calculate energy level, E – Ef, in the conduction band at which the electron density drops to 1 electron/cm3. Use graphical solution at room temperature. Assume effective mass is the same as the electron mass at rest m' = mo = 9.11 × 10¬31 kg.arrow_forwardVolume 2. a) The intrinsic carrier concentration in GaAs at 300 K is 1.8 x 106 cm³. What is the carrier concentration in fm³ at this temperature? b) The mobility of holes in GaAs at 300 K is 400 cm²/V-s. What is the mobility in m²/V-s?arrow_forward
- The Boltzmann constant is k = 8.617 * 10-5 eV/K. For a metallic solid at room temperature (293 K), what is the probability that an electron state is occupied if its energy is 0.100 eV above the Fermi level?arrow_forwarda) Write down a relation giving the number of electrons occupying the energy states between the energy interval dɛ at ɛ. b) What is the probability that a state 0.1 eV above the Fermi level is occupied by an electron at room temperature ? What is the same probability if that state is1 eV above the Fermi level ? c) What is a magnetic moment ? The neutron is a neutral particle, but it has a magnetic moment. Explain why it is so.arrow_forwardAsaplikearrow_forward
- 48 Show that P(E), the occupancy probability in Eq. 41-6, is sym- metrical about the value of the Fermi energy; that is, show that P(EF + AE) + P(EF - AE) = 1.arrow_forwardThe Fermi energy level for a particular material at T = 300 K is 5.50 eV. The electrons in this material follow the Fermi-Dirac distribution function. a) Find the probability of an energy level at 5.50 eV being occupied by an electron. b) Repeat part (a) if the temperature is increased to T = 600 K. (Assume that EF is a constant.). c) Calculate the energy level where probability of finding an electron at room temperature is 70%. d) Calculate the temperature at which there is a 7 percent probability that a state 0.4 eV below the Fermi level will be empty of an electron.arrow_forwardIn a Si semiconductor sample of 200 am length at 600 K the hole concentration as a' function of the sample length follows a quadratic relation of the form p (x) = 1 x1015x, at equilibrium the value of the electric field at 160 jum will be: O 1.935 V/cm O 3.250 V/cm O 5805 V/cm O 55.56 V/cm O 6.450 V/cmarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- University Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStaxModern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage Learning
University Physics Volume 3
Physics
ISBN:9781938168185
Author:William Moebs, Jeff Sanny
Publisher:OpenStax
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning