Introduction To Quantum Mechanics
3rd Edition
ISBN: 9781107189638
Author: Griffiths, David J., Schroeter, Darrell F.
Publisher: Cambridge University Press
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Chapter 6.8, Problem 6.27P
To determine
To show that the position and momentum operator in the Heisenberg picture are given by
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Students have asked these similar questions
The general solution of the Schrodinger equation for a particle confined in
an infinite square-well potential (where V = 0) of width L is
w(x)= C sin kx + Dcos kx
V2mE
k
where C and D are constants, E is the energy of the particle and m is
the mass of the particle. Show that the energy E of the particle inside the
square-well potential is quantised.
Show that if (x) and m(x) are solutions
of the time independent Schrödinger equation,
F(x,t) = n(x)e¯(iEn/h)t + um(x) e (iEm/h)t is a solution of
the time dependent Schrödinger equation.
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.
Chapter 6 Solutions
Introduction To Quantum Mechanics
Ch. 6.1 - Prob. 6.1PCh. 6.2 - Prob. 6.2PCh. 6.2 - Prob. 6.3PCh. 6.2 - Prob. 6.4PCh. 6.2 - Prob. 6.5PCh. 6.2 - Prob. 6.7PCh. 6.4 - Prob. 6.8PCh. 6.4 - Prob. 6.9PCh. 6.4 - Prob. 6.10PCh. 6.4 - Prob. 6.11P
Ch. 6.4 - Prob. 6.12PCh. 6.4 - Prob. 6.13PCh. 6.5 - Prob. 6.14PCh. 6.5 - Prob. 6.15PCh. 6.5 - Prob. 6.16PCh. 6.5 - Prob. 6.17PCh. 6.6 - Prob. 6.18PCh. 6.6 - Prob. 6.19PCh. 6.7 - Prob. 6.20PCh. 6.7 - Prob. 6.21PCh. 6.7 - Prob. 6.22PCh. 6.7 - Prob. 6.23PCh. 6.7 - Prob. 6.25PCh. 6.8 - Prob. 6.26PCh. 6.8 - Prob. 6.27PCh. 6.8 - Prob. 6.28PCh. 6.8 - Prob. 6.30PCh. 6 - Prob. 6.31PCh. 6 - Prob. 6.32PCh. 6 - Prob. 6.34PCh. 6 - Prob. 6.35PCh. 6 - Prob. 6.36PCh. 6 - Prob. 6.37P
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