- #1

- 91

- 0

a) r = 0

b) r = r

_{b}

I confused how this probability function is used. What's the technique here?

Thanks

- Thread starter frankR
- Start date

- #1

- 91

- 0

a) r = 0

b) r = r

I confused how this probability function is used. What's the technique here?

Thanks

- #2

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

The wavefunction Ψ(r) should be in your book. You already stated the definition of the probability density (|Ψ|

- #3

- 91

- 0

Okay, what do I use for A, n, L and x?

If I evaluate x=0 I get 0. But the answer is non-zero.

If I evaluate x=0 I get 0. But the answer is non-zero.

- #4

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

Whoa: What are A, n, and L? Also, don't you mean r instead of x?Originally posted by frankR

Okay, what do I use for A, n, L and x?

If you evaluateIf I evaluate x=0 I get 0. But the answer is non-zero.

- #5

- 91

- 0

|Ψ|

No radial coordinate.

- #6

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

That's the wavefunction for a particle in a box. It isn't applicable to the hydrogen atom. You need to look up that wavefunction, which will certainly have a radial coordinate.Originally posted by frankR

Halliday gives:

(|Ψ|^{2}) = A^{2}Sin^{2}(n:pi:/L * x), n = 1, 2, 3,...

No radial coordinate.

- #7

- 91

- 0

Ψ(r) = 1/(sqrt[[pi]a

Square that and evaulate, or can I just evaluate and squre?

- #8

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

- #9

- 91

- 0

I get: 6.121e^9

- #10

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

And you got your answer how....?

- #11

- 91

- 0

Since a=5.29x10^-11m the answer should be very large.

This must not be the correct formula or something.

- #12

Tom Mattson

Staff Emeritus

Science Advisor

Gold Member

- 5,500

- 8

You should ask yourself:Originally posted by frankR

Since a=5.29x10^-11m the answer should be very large.

It should be very large in what units?

You are working in meters, and the answer was given in inverse cubic nanometers.

- #13

- 91

- 0

HAHHAHA!

That's what happens when you do physics for 10 hours straight.

Edit: BTW, I've never seen that type of unit used before so my brain must have dismissed it.

That's what happens when you do physics for 10 hours straight.

Edit: BTW, I've never seen that type of unit used before so my brain must have dismissed it.

Last edited:

- #14

- 91

- 0

Oh BTW: Thanks for your help Tom.

- Last Post

- Replies
- 1

- Views
- 979

- Last Post

- Replies
- 16

- Views
- 2K

- Replies
- 2

- Views
- 1K

- Last Post

- Replies
- 1

- Views
- 948

- Last Post

- Replies
- 1

- Views
- 3K

- Replies
- 5

- Views
- 4K

- Replies
- 3

- Views
- 21K

- Last Post

- Replies
- 1

- Views
- 2K

- Last Post

- Replies
- 11

- Views
- 1K

- Last Post

- Replies
- 3

- Views
- 1K