Introduction To Quantum Mechanics
3rd Edition
ISBN: 9781107189638
Author: Griffiths, David J., Schroeter, Darrell F.
Publisher: Cambridge University Press
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Question
Chapter 2, Problem 2.38P
(a)
To determine
Show that the wave function of a particle in the infinite square well returns to its original form after quantum revival time
(b)
To determine
The revival time, for a particle of energy bouncing back and forth between the walls.
(c)
To determine
Show that the energy of the two revival times equals.
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Students have asked these similar questions
A particle of mass 1.60 x 10-28 kg is confined to a one-dimensional box of length 1.90 x 10-10 m. For n = 1, answer the following.
(a) What is the wavelength (in m) of the wave function for the particle?
m
(b) What is its ground-state energy (in eV)?
eV
(c) What If? Suppose there is a second box. What would be the length L (in m) for this box if the energy for a particle in the n = 5 state of this box
is the same as the ground-state energy found for the first box in part (b)?
m
(d) What would be the wavelength (in m) of the wave function for the particle in that case?
m
Suppose a particle of mass m is attached to a well of infinite potential.
a) Show that the wave function returns to its original form after a time T = 4ma2/πℏ, i.e.,Ψ(psi)(x, T) = Ψ(psi)(x, 0) for any state (not just stationary states).b) What would be the classical equivalent of T, for a particle of energy E that bounces periodically betweenthe walls of potential?c) For what energy are both times (classical and quantum) equal?
(a) Consider the following wave function of Quantum harmonic oscillator:
3
4
V(x, t) = =Vo(x)e¯iEot +.
Where, Eo, E, are the energy values corresponding to the ground state and the first excited state.
Show that the expectation value of î in this state is periodic in time. What is the period?
(b) Consider a quantum harmonic oscillator. The operator â4 is defined by :
mw
1
â4 =
2h
d:
2ħmw
Find the expectation value of Hamiltonian for the state â4,(x).
ma 1/4,-
x2
and , (x) =
-
mw
ma, x2
[Given ,(x) = ()
mw1/4 2mw
x:
1.
πή
Chapter 2 Solutions
Introduction To Quantum Mechanics
Ch. 2.1 - Prob. 2.1PCh. 2.1 - Prob. 2.2PCh. 2.2 - Prob. 2.3PCh. 2.2 - Prob. 2.4PCh. 2.2 - Prob. 2.5PCh. 2.2 - Prob. 2.6PCh. 2.2 - Prob. 2.7PCh. 2.2 - Prob. 2.8PCh. 2.2 - Prob. 2.9PCh. 2.3 - Prob. 2.10P
Ch. 2.3 - Prob. 2.11PCh. 2.3 - Prob. 2.12PCh. 2.3 - Prob. 2.13PCh. 2.3 - Prob. 2.14PCh. 2.3 - Prob. 2.15PCh. 2.3 - Prob. 2.16PCh. 2.4 - Prob. 2.17PCh. 2.4 - Prob. 2.18PCh. 2.4 - Prob. 2.19PCh. 2.4 - Prob. 2.20PCh. 2.4 - Prob. 2.21PCh. 2.5 - Prob. 2.22PCh. 2.5 - Prob. 2.23PCh. 2.5 - Prob. 2.24PCh. 2.5 - Prob. 2.25PCh. 2.5 - Prob. 2.26PCh. 2.5 - Prob. 2.27PCh. 2.5 - Prob. 2.28PCh. 2.6 - Prob. 2.29PCh. 2.6 - Prob. 2.30PCh. 2.6 - Prob. 2.31PCh. 2.6 - Prob. 2.32PCh. 2.6 - Prob. 2.34PCh. 2.6 - Prob. 2.35PCh. 2 - Prob. 2.36PCh. 2 - Prob. 2.37PCh. 2 - Prob. 2.38PCh. 2 - Prob. 2.39PCh. 2 - Prob. 2.40PCh. 2 - Prob. 2.41PCh. 2 - Prob. 2.42PCh. 2 - Prob. 2.44PCh. 2 - Prob. 2.45PCh. 2 - Prob. 2.46PCh. 2 - Prob. 2.47PCh. 2 - Prob. 2.49PCh. 2 - Prob. 2.50PCh. 2 - Prob. 2.51PCh. 2 - Prob. 2.52PCh. 2 - Prob. 2.53PCh. 2 - Prob. 2.54PCh. 2 - Prob. 2.58PCh. 2 - Prob. 2.63PCh. 2 - Prob. 2.64P
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