Introduction To Quantum Mechanics
3rd Edition
ISBN: 9781107189638
Author: Griffiths, David J., Schroeter, Darrell F.
Publisher: Cambridge University Press
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Chapter 1, Problem 1.15P
To determine
The proof that
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A function of the form e^−gx2 is a solution of the Schrodinger equation for the harmonic oscillator, provided that g is chosen correctly. In this problem you will find the correct form of g.
(a) Start by substituting Ψ = e^−gx2 into the left-hand side of the Schrodinger equation for the harmonic oscillator and evaluating the second derivative.
(b) You will find that in general the resulting expression is not of the form constant × Ψ, implying that Ψ is not a solution to the equation. However, by choosing the value of g such that the terms in x^2 cancel one another, a solution is obtained. Find the required form of g and hence the corresponding energy.
(c) Confirm that the function so obtained is indeed the ground state of the harmonic oscillator and has the correct energy.
A particle is confined in a box of length L as shown in the figure. If the
potential is treated as a perturbation, including the first order
correction, the ground state energy is
(a) E =
ħ²π²
2mL²
+ V
(b) E =
ħ²π² Vo
2mL²
ħ²π² Vo
ħ²π² Vo
(c) E =
+
(d) E =
+
2mL² 4
2mL²
L/2
Normalize the wave function
4(x) =
[Nr2(L−x) 0
Chapter 1 Solutions
Introduction To Quantum Mechanics
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