Calculating Broglie Wavelength for Helium Superfluid

  • Context: Graduate 
  • Thread starter Thread starter glueball8
  • Start date Start date
  • Tags Tags
    Wavelength
Click For Summary

Discussion Overview

The discussion centers on the calculation of the de Broglie wavelength for helium atoms in the context of superfluidity, particularly at temperatures below 2.18 K. Participants explore the relationship between quantum physics and the behavior of superfluids, as well as the implications of the de Broglie wavelength in this phenomenon.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related

Main Points Raised

  • The original poster (OP) seeks an expression for the de Broglie wavelength of helium atoms and questions whether they will understand this concept after completing their current physics textbook.
  • One participant explains that the de Broglie wavelength is defined as λ = h/p, where p is momentum and h is Planck's constant, and suggests that the OP's textbook should cover this topic if it includes modern physics.
  • Another participant introduces the idea of thermal velocity distributions and Bose-Einstein statistics as relevant concepts for understanding superfluids.
  • A different participant expresses familiarity with the de Broglie equation but struggles to apply it to a multiple-choice question, questioning whether K is a constant in the context of their problem.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and familiarity with the de Broglie wavelength and its application to superfluidity. There is no consensus on the specific application of the equation to the OP's question, and some participants raise additional concepts without resolving the initial inquiry.

Contextual Notes

Participants mention the need for a deeper understanding of thermal velocity distributions and statistical mechanics, which may not be fully covered in the OP's current textbook. The discussion reflects a range of assumptions about the OP's background knowledge and the applicability of the de Broglie wavelength in this context.

Who May Find This Useful

This discussion may be useful for students studying quantum physics, particularly those interested in superfluidity and the de Broglie wavelength, as well as those preparing for related homework or exams.

glueball8
Messages
345
Reaction score
1
Helium becomes a super°uid at temperatures T <
2:18 K. A super°uid °ows with no viscosity. This behaviour
can only be explained using quantum physics and it can
only happen if the de Broglie wavelength of a helium atom,
of mass m, is comparable to the inter-atomic spacing of the
°uid. What could be an expression for
the de Broglie wavelength?

Can anyone tell me where to learn this?

I'm currently working on Fundamentals of Physics, would I understand this when I finish the book? What level is this?

Thanks in advance
 
Physics news on Phys.org
The debroglie wavelength is a concept in modern/ quantum physics. If you have an edition of Fundamentals that includes a section on modern physics, then the book should cover the DeBroglie wavelength.

In short, the Debroglie wavelength expresses the wave-particle nature of matter by assigning a wavelength to matter particles. A particle's deBroglie wavelength is given by:

[tex]\lambda_{deBroglie} = \frac{h}{p}[/tex]

where p is the particle's momentum, and h is Planck's constant.

Also, for an introductory summary of the topic:

http://hyperphysics.phy-astr.gsu.edu/Hbase/debrog.html
 
I hadn't thought of super-fluids in that way..

The OP may also want to google for thermal velocity distributions (and Bose-Einstein statistics).
 
oh I know that equation and stuff but I can't get an answer. Its a mutiple choice and I think the (A) Based on it looks like the mv is just changed {answers shown below on the pic I think}.

Is K a constant?
 
Last edited:

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 8 ·
Replies
8
Views
5K
Replies
1
Views
4K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 2 ·
Replies
2
Views
6K
Replies
3
Views
5K
  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K