Wave mechanics: Difference between revisions

From apimba
Jump to navigation Jump to search
Line 4: Line 4:
The basic equation of wave mechanics is a function that describes the position of a particle as a function of time, where the function is wavelike, such as sine or cosine:
The basic equation of wave mechanics is a function that describes the position of a particle as a function of time, where the function is wavelike, such as sine or cosine:


F(x,t) = Ψ = Acos(kx - ωt)
F(x,t) = Ψ = Asin(kx - ωt)


image showing cosine on F,x plane labelled with A, k and ω.
image showing sine on F,x and t 3d plot labelled with A, k and ω.


A = amplitude
A = amplitude
Line 14: Line 14:
w = 2πf
w = 2πf


So if given the amplitude, wavelength and frequency of a particle that was behaving in a cosine fashion, its position could be calculated at a particular time on the t axis using this equation. It would also give the particle position as a function of time at a particular distance on the x axis. Both plots F vs. x and F vs. t would be cosine plots.
So if given the amplitude, wavelength and frequency of a particle that was behaving in a sine fashion, its position could be calculated at a particular time on the t axis using this equation. It would also give the particle position as a function of time at a particular distance on the x axis. Both plots F vs. x and F vs. t would be cosine plots.

Revision as of 11:52, 5 May 2020

Introduction

Basic Equation

The basic equation of wave mechanics is a function that describes the position of a particle as a function of time, where the function is wavelike, such as sine or cosine:

F(x,t) = Ψ = Asin(kx - ωt)

image showing sine on F,x and t 3d plot labelled with A, k and ω.

A = amplitude

k = 2π/λ

w = 2πf

So if given the amplitude, wavelength and frequency of a particle that was behaving in a sine fashion, its position could be calculated at a particular time on the t axis using this equation. It would also give the particle position as a function of time at a particular distance on the x axis. Both plots F vs. x and F vs. t would be cosine plots.