(a)
To show: When the Fermi energy at absolute zero is
(b)
Whether the ignoring the relativistic effects is a good approximation for electrons in metals such as copper.
(c)
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)
Whether ignoring the relativistic effects is a good approximation in the structure of a white dwarf star.
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University Physics with Modern Physics, Books a la Carte Edition; Modified MasteringPhysics with Pearson eText -- ValuePack Access Card -- for ... eText -- Valuepack Access Card (14th Edition)
- 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
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- University Physics Volume 3PhysicsISBN:9781938168185Author:William Moebs, Jeff SannyPublisher:OpenStaxModern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage Learning