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Homework Help: Particle in box

  1. Oct 23, 2008 #1
    1. The problem statement, all variables and given/known data

    A particle is trapped in an infinite one-dimensional square well which extends between x=0 and x=a. If the particle is in the ground state, calculate the probability that it is between 0.4a and 0.6a.

    2. The attempt at a solution

    The normalised of the ground state is sqrt((2/a)sin(pi*x/a)

    Setting k = pi/a, I get the probability

    (2/a)Int(sin^2(kx)dx for 0.4 - 0.6. How can I solve this integral?
  2. jcsd
  3. Oct 23, 2008 #2

    George Jones

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    Staff Emeritus
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    Gold Member

    If you've taken first-year integral calculus, you have seen this type of integral. Do you know any trig identities that involve [itex]sin^2 \theta[/itex]?
  4. Oct 23, 2008 #3
    sin2x = (1-cos2x)/2 and then integrate.

    May be someone said that:
    "Physics is too tough for Physicists."
    ... may be he was Schrodinger.
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