# The Naked Scientists Forum

### Author Topic: How was the direction of force lines determined?  (Read 1593 times)

#### Ron Hughes

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##### How was the direction of force lines determined?
« on: 15/04/2010 14:38:19 »
I have read that the field force lines of an electron point to the electron and away from the proton. Can someone tell me the experiment that determined this or was it just a matter of convention?

#### yor_on

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##### How was the direction of force lines determined?
« Reply #1 on: 23/04/2010 12:24:09 »
Where did you read it Ron?

"Two electrons will tend to repel each other because both have a negative electrical charge. Two protons will also tend to repel each other because they both have a positive charge. On the other hand, electrons and protons will be attracted to each other because of their unlike charges."

The force lines I've seen depicted is pointing outward, not bending in on themselves as I think you describe for the electron? That sounds more like the magnetic field created when the electron is moving??

==
Then again, was it that you meant :)
« Last Edit: 23/04/2010 12:25:47 by yor_on »

#### Murchie85

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• Posts: 124
##### How was the direction of force lines determined?
« Reply #2 on: 23/04/2010 23:32:37 »
If I remember correctly, electric field lines start on a positive charge i.e a proton and end on a negative charge such as an electron. They can be thought of as lines mapping out the direction of travel a positive test charge (one with an infintesimal charge size as not to generate a field of its own)would move if placed in the local region. Things to remember is lines do not overlap, they never start or end on infinity and they ARE NOT FORCES although they do represent the direction of force. Electromagnetism can be analogous to gravity in that a large body (i.e planet) displaces the space around it in which everything else is effected within the local vicinity, in a similar way a proton would effect other charged bodies in its region, the main difference being that the force can be attractive and repulsive.
Hope this helps.