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Is an Electron a Particle or a Wave?

Date: 12/02/1999 at 19:14:29
From: Aleem
Subject: Electron: particle or wave?

Can you explain to me whether the electron is a particle or a wave? 
Electrons diffract, and diffraction is a property of a wave. However 
electrons also have a mass, something waves don't have. How does this 
work? Could the electron be a quantum wave kind of like light?


Date: 12/04/1999 at 13:10:56
From: Doctor Jeremiah
Subject: Re: Electron: particle or wave?

Hi Aleem:

This is primarily a science question, so perhaps you would be better 
off going to a science site. Having said that, however, I will try to 
answer your question.

Everything is a wave and a particle. Everything. But the more mass an 
object has, the smaller the waves. Electrons don't have much mass so 
their waves are big enough to see.

On the other hand, light is a wave and a particle. Light does have 
mass. Its mass is zero when the light is not moving, but that never 
happens because light always moves at the speed of light.

The mass of light moving at the speed of light can be measured and is 
dependant on the wavelength:

     m = hw/c

where:  h is Plank's constant
        w is the wavelength
        c is the speed of light

In the same way the size of the electrons waves can be measured:

     w = mv/h

where:  h is Plank's constant
        w is the wavelength
        v is the speed of the electron

When an electron is travelling in orbit around a nucleus it is 
restricted to speeds that make orbits containing an integral number of 
waves. This is what creates the different electron "shells" in an 

Good luck on finding the answers you seek.

- Doctor Jeremiah, The Math Forum   
Associated Topics:
High School Physics/Chemistry

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