Understanding the Ohm: Definition, Explanation, and Examples

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The ohm is defined as the resistance between two points in a conductor when a potential difference of 1 volt causes a current of 1 ampere. The discussion highlights confusion over the definition, emphasizing that it describes how much current is produced rather than how much is prevented. The analogy of potential energy, like a rock on a cliff, illustrates how voltage represents stored energy that drives current flow. A resistance of 1 ohm corresponds to 1 amp being allowed through with a 1-volt potential difference, while higher resistance results in lower current for the same voltage. Overall, the lower the ohm value, the lower the resistance, clarifying the relationship between voltage, current, and resistance.
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The ohm is defined as a resistance between two points of a conductor when a constant potential difference of 1 volt, applied to these points, produces in the conductor a current of 1 ampere, the conductor not being the seat of any electromotive force.

I'm not sure I understand this definition, it's written in a rather confusing manner...instead of saying how much ampere is being stopped from flowing, it tells us how much current is being produced!

That's a little confusing...I thought the definition for the resistance SI unit would be how much of the current is prevented...as in a negative number, maybe.
 
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Well, a volt is a POTENTIAL energy. Like say there is a rock on top of a cliff. It has a potential energy, if it were pushed off the edge the potential energy would be converted into kinetic energy.

So, the volt is like a store of charge at one side of a material that wants to go to the side with less charge. (i.e. the rock falling off the cliff to get to a lower energy). If the material slows the charge to move at 1 amp = (1couloumb/sec). The materials resistance will be 1 ohm.

So if the material slowed the charges trying to get to the other side to .1 amps. The materials resistance would be higher... ( 1/.1 = 10 ohms).
 
So let me see if I get it right:

1 ohm is 1 amp being stopped per volt, whereas 2 ohm is 2 amp being stopped per volt?...etc etc
 
not being stopped. being allowed through the material. if 1 amp is being allowed through with a 1 volt potential difference. the resistance is 1 ohm. if 2 amps are being allowed through with a potential difference of 1 volt. The resistance is 1volt/2amps. = 1/2 ohm.

The units for OHM = VOLT/AMP
 
Ah, makes complete sense...so the lower the ohm the lower the resistance right? right. I see now :) thanks.
 
If you are interested in the http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html" ,

micohm.gif


check this out.
 

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