What Is the Probability of Finding a Particle in the Interval [0,d]?

Click For Summary

Homework Help Overview

The discussion revolves around calculating the probability of finding a particle in a specified interval based on its wavefunction in one-dimensional quantum mechanics. The wavefunction is given as Ae^{-\frac{|x|}{2d}}, and participants are tasked with determining the probability in the interval [0,d] while ensuring normalization of the wavefunction.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the normalization of the wavefunction and the subsequent integration to find the probability in the specified interval. There are questions regarding the correctness of the normalization constant A and the integration process, particularly concerning the exponent in the exponential function.

Discussion Status

Some participants are verifying their calculations and checking for errors in the normalization process. There is an ongoing exploration of the integration steps, with corrections being made based on feedback from others. The discussion reflects a collaborative effort to clarify the mathematical reasoning involved.

Contextual Notes

Participants are working under the assumption that A is a real number and are required to express their answers in terms of A, d, and relevant mathematical constants. There is an emphasis on ensuring the wavefunction is properly normalized before calculating probabilities.

Nugso
Gold Member
Messages
170
Reaction score
10

Homework Statement



Suppose we have a particle in 1-dimension, with wavefunction [tex]Ae^{-\frac{|x|}{2d}}[/tex] . What is the probability to find the particle in the interval [0,d]?
Please provide your answer in terms of A, d, mathematical constants such as π (entered as pi) or e (entered as e). (Assume that A is real)



Homework Equations



[tex]∫ψ²dx = 1[/tex]




The Attempt at a Solution



I think I need to find A by normalizing it. [tex]∫ψ²dx = 1[/tex]

By integrating it, I get [tex]A= 1/\sqrt{2d}[/tex]

Now, I have to integrate it again, but this time with the interval of [0,d]

[tex]∫1/sqrt(2d)*e^{-\frac{|x|}{2d}}*1/sqrt(2d)*e^{-\frac{|x|}{2d}}dx[/tex]

and the answer I'm finding is, [tex]1/2*(1-e^{-1/d})*d[/tex]

But somehow the answer is wrong. How do I correct it?
 
Last edited:
Physics news on Phys.org
I would check your solution for A again.
 
  • Like
Likes   Reactions: 1 person
Nugso said:

Homework Statement



Suppose we have a particle in 1-dimension, with wavefunction [tex]Ae^{-\frac{|x|}{2d}}[/tex] . What is the probability to find the particle in the interval [0,d]?
Please provide your answer in terms of A, d, mathematical constants such as π (entered as pi) or e (entered as e). (Assume that A is real)



Homework Equations



[tex]∫ψ²dx = 1[/tex]




The Attempt at a Solution



I think I need to find A by normalizing it. [tex]∫ψ²dx = 1[/tex]

By integrating it, I get [tex]A= 1/\sqrt{2d}[/tex]

Now, I have to integrate it again, but this time with the interval of [0,d]

[tex]∫1/sqrt(2d)*e^{-\frac{|x|}{2d}}*1/sqrt(2d)*e^{-\frac{|x|}{2d}}dx[/tex]

and the answer I'm finding is, [tex]1/2*(1-e^{-1/d})*d[/tex]

But somehow the answer is wrong. How do I correct it?

Check it again. How did you wind up with a -1/d in the exponent?
 
  • Like
Likes   Reactions: 1 person
Sorry for the late reply. I checked it and corrected the mistake.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
3K
Replies
16
Views
3K
Replies
13
Views
3K
Replies
19
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
3
Views
2K
  • · Replies 23 ·
Replies
23
Views
3K