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 2.2, Problem 2.5P
(a)
To determine
The normalization of
(b)
To determine
The value of
(c)
To determine
The value of
(d)
To determine
The value of
(e)
To determine
The energy of the particle, the probability of getting each of them, the expected value of
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A particle in the infinite square well has as its initial wave function an
even mixture of the first two stationary states:
(x,0) = A [v₁ (x) + ₂(x)].
(a) Normalize (x, 0). (That is, find A. This is very easy, if you exploit the
orthonormality of 1 and 2. Recall that, having normalized at t = 0,
you can rest assured that it stays normalized—if you doubt this, check it
explicitly after doing part (b).)
(c)
(b) Find (x, t) and (x, t)|². Express the latter as a sinusoidal function
of time, as in Example 2.1. To simplify the result, let w = ²ħ/2ma².
Compute (x). Notice that it oscillates in time. What is the angular
frequency of the oscillation? What is the amplitude of the oscillation? (If
your amplitude is greater than a /2, go directly to jail.)
(d) Compute (p). (As Peter Lorre would say, "Do it ze kveek vay, Johnny!”)
(e) If you measured the energy of this particle, what values might you get,
and what is the probability of getting each of them? Find the expectation
value of H. How does…
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.
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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