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roshan2004
Jun19-10, 10:43 AM
1. The problem statement, all variables and given/known data

A particle is moving in a one dimensional box of infinite height of width 10 Angstroms. Calculate the probability of finding the particle within an interval of 1 Angstrom at the centre of the box, when it is in its state of least energy.

2. Relevant equations


\psi _{n}=\sqrt{\frac{2}{L}}sin \frac{n\pi x}{L}


3. The attempt at a solution
The wave function of the particle in the ground state (n=1) is \psi _{1}=\sqrt{\frac{2}{L}}sin \frac{\pi x}{L}. Now, what should I do ?

Feldoh
Jun19-10, 12:06 PM
How does one find the probability amplitude in QM?

roshan2004
Jun19-10, 12:18 PM
Square of its wavefunction. I got <tex> \frac{2}{L}sin^2 \frac{\pi x}{L}</tex> Now...........

Feldoh
Jun19-10, 01:18 PM
Okay, now how do you find the probability on the interval [4 Angstroms,6 Angstroms]?

roshan2004
Jun19-10, 01:28 PM
Why between 4 and 6 angstroms ?

Feldoh
Jun19-10, 01:56 PM
Why do you think it's between 4 and 6 angstroms?

EDIT: Err rather I believe it should be from 4.5 to 5.5 angstroms...

graphene
Jun20-10, 08:20 AM
probability of finding the particle between x & x+dx is {|\Psi|}^{2}

probability of finding the particle between x=a and a=b is \int_{a}^{b}{|\Psi|}^{2}dx

roshan2004
Jun20-10, 09:21 AM
What are the limits I should use for the integration?

graphene
Jun22-10, 01:09 AM
Find a and b for "an interval of 1 Angstrom at the centre of the box".