Principles of Physics: A Calculus-Based Text, Hybrid (with Enhanced WebAssign Printed Access Card)
5th Edition
ISBN: 9781305586871
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 28, Problem 72P
To determine
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In quantum mechanics, the probability of finding a particle æ in domain (a, b) can
be calculated from the following formula
P(a < # < b) = / Mla
p(x)dr
where the probability density p(a') satisfies p(x) « 1/x for æ e (1, e²) and being 0 elsewhere.
Please determine the exact form of the probability density and calculate the probability of
finding a particle in domain [1, 2).
A particle with mass m is moving in three-dimensions under the potential energy U(r), where
r is the radial distance from the origin. The state of the particle is given by the time-independent
wavefunction,
Y(r) = Ce-kr.
Because it is in three dimensions, it is the solution of the following time-independent
Schrodinger equation
dıp
r2
+ U(r)µ(r).
dr
h2 d
EÞ(r) =
2mr2 dr
In addition,
00
1 =
| 4ar?y? (r)dr,
(A(r)) = | 4r²p²(r)A(r)dr.
a. Using the fact that the particle has to be somewhere in space, determine C. Express your
answer in terms of k.
b. Remembering that E is a constant, and the fact that p(r) must satisfy the time-independent
wave equation, what is the energy E of the particle and the potential energy U(r). (As
usual, E and U(r) will be determined up to a constant.) Express your answer in terms of
m, k, and ħ.
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
EV,
2m dx²
with boundary conditions (0) = 0 and V(1) = 0.
Second, the Quantum Harmonic Oscillator (QHO)
=
h² d²
+kr²V = EV
2m dg²+ka²
1/ k2²) v
(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.
Chapter 28 Solutions
Principles of Physics: A Calculus-Based Text, Hybrid (with Enhanced WebAssign Printed Access Card)
Ch. 28.1 - Prob. 28.1QQCh. 28.2 - Prob. 28.2QQCh. 28.2 - Prob. 28.3QQCh. 28.2 - Prob. 28.4QQCh. 28.5 - Prob. 28.5QQCh. 28.5 - Prob. 28.6QQCh. 28.6 - Prob. 28.7QQCh. 28.10 - Prob. 28.8QQCh. 28.10 - Prob. 28.9QQCh. 28.13 - Prob. 28.10QQ
Ch. 28 - Prob. 1OQCh. 28 - Prob. 2OQCh. 28 - Prob. 3OQCh. 28 - Prob. 4OQCh. 28 - Prob. 5OQCh. 28 - Prob. 6OQCh. 28 - Prob. 7OQCh. 28 - Prob. 8OQCh. 28 - Prob. 9OQCh. 28 - Prob. 10OQCh. 28 - Prob. 11OQCh. 28 - Prob. 12OQCh. 28 - Prob. 13OQCh. 28 - Prob. 14OQCh. 28 - Prob. 15OQCh. 28 - Prob. 16OQCh. 28 - Prob. 17OQCh. 28 - Prob. 18OQCh. 28 - Prob. 1CQCh. 28 - Prob. 2CQCh. 28 - Prob. 3CQCh. 28 - Prob. 4CQCh. 28 - Prob. 5CQCh. 28 - Prob. 6CQCh. 28 - Prob. 7CQCh. 28 - Prob. 8CQCh. 28 - Prob. 9CQCh. 28 - Prob. 10CQCh. 28 - Prob. 11CQCh. 28 - Prob. 12CQCh. 28 - Prob. 13CQCh. 28 - Prob. 14CQCh. 28 - Prob. 15CQCh. 28 - Prob. 16CQCh. 28 - Prob. 17CQCh. 28 - Prob. 18CQCh. 28 - Prob. 19CQCh. 28 - Prob. 20CQCh. 28 - Prob. 1PCh. 28 - Prob. 2PCh. 28 - Prob. 3PCh. 28 - Prob. 4PCh. 28 - Prob. 6PCh. 28 - Prob. 7PCh. 28 - Prob. 8PCh. 28 - Prob. 9PCh. 28 - Prob. 10PCh. 28 - Prob. 11PCh. 28 - Prob. 13PCh. 28 - Prob. 14PCh. 28 - Prob. 15PCh. 28 - Prob. 16PCh. 28 - Prob. 17PCh. 28 - Prob. 18PCh. 28 - Prob. 19PCh. 28 - Prob. 20PCh. 28 - Prob. 21PCh. 28 - Prob. 22PCh. 28 - Prob. 23PCh. 28 - Prob. 24PCh. 28 - Prob. 25PCh. 28 - Prob. 26PCh. 28 - Prob. 27PCh. 28 - Prob. 29PCh. 28 - Prob. 30PCh. 28 - Prob. 31PCh. 28 - Prob. 32PCh. 28 - Prob. 33PCh. 28 - Prob. 34PCh. 28 - Prob. 35PCh. 28 - Prob. 36PCh. 28 - Prob. 37PCh. 28 - Prob. 38PCh. 28 - Prob. 39PCh. 28 - Prob. 40PCh. 28 - Prob. 41PCh. 28 - Prob. 42PCh. 28 - Prob. 43PCh. 28 - Prob. 44PCh. 28 - Prob. 45PCh. 28 - Prob. 46PCh. 28 - Prob. 47PCh. 28 - Prob. 48PCh. 28 - Prob. 49PCh. 28 - Prob. 50PCh. 28 - Prob. 51PCh. 28 - Prob. 52PCh. 28 - Prob. 53PCh. 28 - Prob. 54PCh. 28 - Prob. 55PCh. 28 - Prob. 56PCh. 28 - Prob. 57PCh. 28 - Prob. 58PCh. 28 - Prob. 59PCh. 28 - Prob. 60PCh. 28 - Prob. 61PCh. 28 - Prob. 62PCh. 28 - Prob. 63PCh. 28 - Prob. 64PCh. 28 - Prob. 65PCh. 28 - Prob. 66PCh. 28 - Prob. 67PCh. 28 - Prob. 68PCh. 28 - Prob. 69PCh. 28 - Prob. 70PCh. 28 - Prob. 71PCh. 28 - Prob. 72PCh. 28 - Prob. 73PCh. 28 - Prob. 74P
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