# Homework Help: Probabilistic interpretation of wave function

1. Oct 26, 2008

### briteliner

1. The problem statement, all variables and given/known data
a particle moving in one dimension between rigid walls separated by a distance L has the wave function $$\Psi$$(x)=Asin($$\Pi$$x/L), since the particle must remain between the walls, what must be the value of A?

2. Relevant equations

3. The attempt at a solution

Ok so I'm thinking that since the particle has to be between x=0 and x=1, i should set the probability function = to one for these limits on the integral. i'm really confused on how to do that though

2. Oct 26, 2008

### G01

What must the following integral be equal to according to the probability interpretation of the wave function?

$$\int_0^L\Psi^*\Psi dx=?$$

3. Oct 26, 2008

### briteliner

1? to get psi* what do i do?

thanks

4. Oct 27, 2008

### gulsen

The star means complex conjugate: replaces all $i$s with $-i$s. In your case, $\psi^* = A^* sin(\pi x / L)$, but you can take$A$ to be real, making $\psi = \psi^*$.

5. Oct 27, 2008

### briteliner

okay, thanks a lot

6. Oct 27, 2008

### G01

Yes, that integral is equal to 1. You now, need to evaluate that and figure out what A must be for that expression to be true.

(I have been busy today and I see I'm a little late to respond. I hope you were able to figure it out.)