Electron wave function and Probability

AI Thread Summary
The discussion focuses on calculating the normalization constant, c, for an electron's wave function and determining the probability of finding the electron within a specified range. The user initially calculated c as 0.577 but doubts its accuracy, having derived it from the area under the |ψ|² graph. They also calculated the probability of the electron being between x=-1 and x=1 nm as 0.666, which they believe is incorrect. A participant suggests reevaluating the areas of the rectangles in the wave function graph to clarify the calculations. The user expresses a need for additional examples to better understand wave functions and their properties.
bayan
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Homework Statement



I've been asked to find the value of c and the probability that the electron is located in the range of x=-1 and x=1.

Homework Equations



See Graph below

The Attempt at a Solution



ψ graph http://img850.imageshack.us/img850/61/wavefunction.jpg

|ψ|^{2} graph http://img35.imageshack.us/img35/6663/psisquare.png
As mentioned by ehild the graph is not drawn with correct scale (my carelessness, which caused all my problems)

For part a) I need to find value of C. Which I have found to be 0.577 but the answer seems wrong, I have done this by drawing a |ψ|^{2} graph (which is almost the same except there are no negative y values. I have found c by making the area underneath |ψ|^{2} equal to 1. Since the two smaller square in -1to -2 and 1 to 2 are exactly half I tried to find c by making the graph a rectangle with L=3nm given area must equal 1, width must equal \frac{1}{3}. Hence I got a value for c which is \sqrt{\frac{1}{3}} = 0.577
For part b I am asked to fin probability of electron being in x=-1 and x=1 nm. My answer was 0.666 (0.7 as I have been asked to answer in one significant figure) but this seems wrong too.

Anyone able to tell me where I have made mistake?

Thanks
 
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bayan said:
For part a) I need to find value of C. Which I have found to be 0.577 but the answer seems wrong, I have done this by drawing a |ψ|^{2} graph (which is almost the same except there are no negative y values.

... and the height of the middle part is 4 times the height of the small rectangles. So you have got two rectangles of width 1 and height c2/4 and a big rectangle of width 2 and height c2.
What is the area?


ehild
 
ehild said:
... and the height of the middle part is 4 times the height of the small rectangles. So you have got two rectangles of width 1 and height c2/4 and a big rectangle of width 2 and height c2.
What is the area? ehild
Thanks.

Edit: Obviously I need to work a bit more on wave functions and finding the heights, anyone know where I could get some examples? I tried google, but it comes up with complex stuff.
 
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