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 7.1, Problem 7.1P
(a)
To determine
The first order correction for energy and the reason for the absence of energy for the even value of n.
(b)
To determine
The first three terms in the expansion for the equation 7.13.
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For a particle in a 1-dimensional infinitely deep box of length L, the normalized wave function or the 1st excited state can be written as:
Ψ2(x) = {1/i(2L)1/2} ( eibx -e-ibx), where b = 2π/L.
Give the full expression that you need to solve to determine the probalibity of finding the particle in the 1st third of the box. Simplify as much as possible but do not solve any integrals.
An atom in an infinite potential well of width L=207 pm (from x=0 to x=207 pm) is in the normalised superposition state we considered in class, i.e. ψ=(ψ1+ψ2)/21/2, what is the expectation of the position of the particle, in pm, at time 0.224 (in units of the ground state period, T1)? Hint: use symmetry, a product of sines is the sum of two cosines, and that the integral of x cos(a x) is x sin(a x)/a+cos(a x)/a2. Remember your answer is (hopefully!) between 0 and 207. The part of the answer that is a time-dependent function should have amplitude 16 L/(3π)2.
Problem 2.
Consider the double delta-function potential
V(x) = a[8(x + a) + 8(x − a)],
where a and a are positive constants.
(a) Sketch this potential.
(b) How many bound states does it possess? Find the allowed energies, for a =
ħ²/ma and for a = ħ²/4ma, and sketch the wave functions.
Chapter 7 Solutions
Introduction To Quantum Mechanics
Ch. 7.1 - Prob. 7.1PCh. 7.1 - Prob. 7.2PCh. 7.1 - Prob. 7.3PCh. 7.1 - Prob. 7.4PCh. 7.1 - Prob. 7.5PCh. 7.1 - Prob. 7.6PCh. 7.2 - Prob. 7.8PCh. 7.2 - Prob. 7.9PCh. 7.2 - Prob. 7.10PCh. 7.2 - Prob. 7.11P
Ch. 7.2 - Prob. 7.12PCh. 7.2 - Prob. 7.13PCh. 7.3 - Prob. 7.15PCh. 7.3 - Prob. 7.16PCh. 7.3 - Prob. 7.17PCh. 7.3 - Prob. 7.18PCh. 7.3 - Prob. 7.19PCh. 7.3 - Prob. 7.20PCh. 7.3 - Prob. 7.21PCh. 7.3 - Prob. 7.22PCh. 7.4 - Prob. 7.23PCh. 7.4 - Prob. 7.24PCh. 7.4 - Prob. 7.25PCh. 7.4 - Prob. 7.26PCh. 7.4 - Prob. 7.27PCh. 7.4 - Prob. 7.28PCh. 7.4 - Prob. 7.29PCh. 7.5 - Prob. 7.31PCh. 7.5 - Prob. 7.32PCh. 7 - Prob. 7.33PCh. 7 - Prob. 7.34PCh. 7 - Prob. 7.35PCh. 7 - Prob. 7.36PCh. 7 - Prob. 7.37PCh. 7 - Prob. 7.38PCh. 7 - Prob. 7.39PCh. 7 - Prob. 7.40PCh. 7 - Prob. 7.42PCh. 7 - Prob. 7.43PCh. 7 - Prob. 7.44PCh. 7 - Prob. 7.45PCh. 7 - Prob. 7.46PCh. 7 - Prob. 7.47PCh. 7 - Prob. 7.49PCh. 7 - Prob. 7.50PCh. 7 - Prob. 7.51PCh. 7 - Prob. 7.52PCh. 7 - Prob. 7.54PCh. 7 - Prob. 7.56PCh. 7 - Prob. 7.57P
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