What is the relationship between frequency and energy in matter waves?

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Discussion Overview

The discussion revolves around the relationship between frequency and energy in matter waves, specifically examining the equation f = E/h. Participants explore the meaning of E in this context, questioning whether it represents total energy, rest energy, or kinetic energy, and how these concepts relate to the Schrödinger equation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants question the definition of E in the equation f = E/h, asking if it refers to total energy or just kinetic energy.
  • One participant argues that E does not include potential energy, while another asserts that it includes both kinetic and potential energy in certain contexts.
  • A participant expresses confusion regarding the inclusion of rest energy in the Schrödinger equation, suggesting that it complicates their understanding of free particles.
  • Another participant points out that the equation E = ħν is typically associated with photons, leading to further exploration of the relationship between wavelength, momentum, and frequency.
  • Some participants emphasize the importance of context when quoting equations, suggesting that the application of the equation can vary based on the discussion topic.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the meaning of E in the equation f = E/h, with multiple competing views regarding the inclusion of rest energy and the interpretation of the Schrödinger equation. The discussion remains unresolved.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about energy definitions, the dependence on specific contexts for the equations, and the unresolved mathematical steps related to the Schrödinger equation.

VHAHAHA
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in my book ,their is a equation

f= E/h

what is the E means?
Total energy?
Does it includes the rest energy ?
 
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VHAHAHA said:
in my book ,their is a equation

f= E/h

what is the E means?
Total energy?
Does it includes the rest energy ?

This is a good place for you to learn a bit more on how we do things on here.

Never, ever simply quote an equation without proper context.

For example, under what type of discussion was this equation used? Was it trying to explain the energy of photons? Or was it for some other purposes? Have you seen this equation before with regards to photon energy? Etc... etc... Can you see why simply dumping that equation out of nowhere provides us very little to go on with regards to what YOU are seeing in your text?

Zz.
 
VHAHAHA said:
in my book ,their is a equation

f= E/h

what is the E means?
Total energy?
Does it includes the rest energy ?
It is not the total energy since it does not include a potential energy term. However it does incluideit does include kinetic energy.

If, h = Planck's constant and f =frequency of matter wave, then

E = "inertial energy" = Kinetic Energy + Rest Energy
 
It is not the total energy since it does not include a potential energy term. However it does incluideit does include kinetic energy.
:confused: Of course it includes both kinetic and potential energy. A stationary state for a particle in a potential well is described by ψ ~ exp(iEt/ħ) where E is an eigenvalue of H = p2/2m + V(x).
 
if the terms includes rest energy
i will not understand the Schrödinger equation
the Schrödinger equ
if the terms includes rest energy i will not understand the Schrödinger equation the Schrödinger equ for free particle
[PLAIN]http://hyperphysics.phy-astr.gsu.edu/%E2%80%8Chbase/quantum/imgqua/seq1.gif
for free particle U=0 and the second term is eliminated
and
http://hyperphysics.phy-astr.gsu.edu/%E2%80%8Chbase/quantum/imgqua/seq2.gif
sub ψ into the Schrödinger equ for free particle
and take the derivative
we got
(ħ^2)(k^2) / 2m = ħw
if E= homework = rel. energy
why can i get (ħ^2)(k^2) / 2m = ħw?
i mean, (ħ^2)(k^2) / 2m = p^2/2m where p is the momentum
and E will be equal to non-rel. KE energy only , but there is no rest energy included!
Plz help =(

STEPS are included


reference: Modern physics second edition , international ed, RANDY HARRIS p.110 - 112
 

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ZapperZ said:
This is a good place for you to learn a bit more on how we do things on here.

Never, ever simply quote an equation without proper context.

For example, under what type of discussion was this equation used? Was it trying to explain the energy of photons? Or was it for some other purposes? Have you seen this equation before with regards to photon energy? Etc... etc... Can you see why simply dumping that equation out of nowhere provides us very little to go on with regards to what YOU are seeing in your text?

Zz.


Actually, i originally think that it refers to KE+rest energy , ie rel. energy
but what i get from the Schrödinger equation for free particles tells that E= non-rel. KE only

you can see the reply for more details. Plz help me, i spend a week to find the ans but i still can figure it out
 
Isn't the equation E= ħ∨ used for photon

In my knowledge ,
we first calculate λ from λ= ħ/p , then use equation v=λ∨ ==> λ=v/∨
==>
v/∨=ħ/p
==>
∨=pv/h
==>
∨=mv2/h
 

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