Modern Physics
3rd Edition
ISBN: 9781111794378
Author: Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher: Cengage Learning
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Chapter 6, Problem 24P
(a)
To determine
The expression for
(b)
To determine
The normalization constant of the wave.
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Problem 3. Consider the two example systems from quantum mechanics. First, for a
particle in a box of length 1 we have the equation
h² d²v
2m dx²
EV,
with boundary conditions (0) = 0 and (1) = 0.
Second, the Quantum Harmonic Oscillator (QHO)
V = EV
h² d²
2m da² +ka²)
1
+kx²
2
(a) Write down the states for both systems. What are their similarities and differences?
(b) Write down the energy eigenvalues for both systems. What are their similarities
and differences?
(c) Plot the first three states of the QHO along with the potential for the system.
(d) Explain why you can observe a particle outside of the "classically allowed region".
Hint: you can use any state and compute an integral to determine a probability of
a particle being in a given region.
= =
An electron having total energy E 4.60 eV approaches a rectangular energy barrier with U■5.10 eV and L-950 pm as shown in the figure below. Classically, the electron cannot pass through the barrier
because E < U. Quantum-mechanically, however, the probability of tunneling is not zero.
Energy
E
U
0
i
(a) Calculate this probability, which is the transmission coefficient. (Use 9.11 x 10-31 kg for the mass of an electron, 1.055 x 10-34] s for h, and note that there are 1.60 x 10-19
J per eV.)
(b) To what value would the width L of the potential barrier have to be increased for the chance of an incident 4.60-eV electron tunneling through the barrier to be one in one million?
nm
In a certain region of space, a particle is described by the wave function ψ=Cxe−bx where C is a real constants, b =0.5, and m=3.2. By substituting into the Schrodinger equation, find the potential energy (not necessarily constant) in this region and also find the energy of the particle. (Hint: Your solution must give an energy that is a constant everywhere in this region, independent of x.)
Chapter 6 Solutions
Modern Physics
Ch. 6.4 - Prob. 1ECh. 6.4 - Prob. 2ECh. 6.5 - Prob. 4ECh. 6.7 - Prob. 5ECh. 6.8 - Prob. 6ECh. 6 - Prob. 1QCh. 6 - Prob. 2QCh. 6 - Prob. 3QCh. 6 - Prob. 4QCh. 6 - Prob. 5Q
Ch. 6 - Prob. 6QCh. 6 - Prob. 7QCh. 6 - Prob. 8QCh. 6 - Prob. 1PCh. 6 - Prob. 2PCh. 6 - Prob. 3PCh. 6 - Prob. 5PCh. 6 - Prob. 6PCh. 6 - Prob. 7PCh. 6 - Prob. 8PCh. 6 - Prob. 9PCh. 6 - Prob. 10PCh. 6 - Prob. 11PCh. 6 - Prob. 12PCh. 6 - Prob. 13PCh. 6 - Prob. 14PCh. 6 - Prob. 15PCh. 6 - Prob. 16PCh. 6 - Prob. 17PCh. 6 - Prob. 18PCh. 6 - Prob. 19PCh. 6 - Prob. 21PCh. 6 - Prob. 24PCh. 6 - Prob. 25PCh. 6 - Prob. 26PCh. 6 - Prob. 28PCh. 6 - Prob. 29PCh. 6 - Prob. 30PCh. 6 - Prob. 31PCh. 6 - Prob. 32PCh. 6 - Prob. 33PCh. 6 - Prob. 34PCh. 6 - Prob. 35PCh. 6 - Prob. 37PCh. 6 - Prob. 38P
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