# Understanding electricity?

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I really don't have even a good idea of how Amps, Watts, and Volts work together. I'd like to learn what each is/does and how they relate and work together. Does anyone know a good guide or tutorial?
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#### slow'puter

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A guide, no, but I know this:

Amperage is the measurement of electrical current. Think of it as a flow of water.
Watts is the measurement of electrical power. It is an indirect relationship between amperage and time (A/t = W). Think of it as the force water carries.
Voltage is a little bit complicated to explain. It is the measure of energy per chage unit. Think of it as the difference in the energies of the positive and negative terminals of a battery.

In order to create work (Watts), you must have a resistor. From Ohm's Law:

V=IR

Ohm's Law demonstrates that for every voltage there is a corresponding current if the resistance is constant. So in a PSU, the resistors in a given rail will determine the voltage (12, 5.5 or 3 volts). The amperage rating is the amount of current flowing to create that particular volatge. Current control is crucial to keep clean power and stable readings. The wattage is the ultimate result of the work performed by the resistors in all rails; higher power ratings indicate the PSU can put out more work because it can handle higher currents.

Hope it is clear enough.

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Ok, so let me try to break it down. I'm still a bit confused, mostly with volts, of course, but....

If it were a river, I'd say that the depth and width of the water (amount in the river at once, or wire as far as electricity goes) are the amps. Watts are the force at which the water (electricity) is travelling from a source?

#### zone

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Quote:
 Originally Posted by CanadaGradeEh Ok, so let me try to break it down. I'm still a bit confused, mostly with volts, of course, but.... If it were a river, I'd say that the depth and width of the water (amount in the river at once, or wire as far as electricity goes) are the amps. Watts are the force at which the water (electricity) is travelling from a source?
If we were to compare electricity passing through a wire to the Niagara Falls...
Amps would be how fast the water is falling down (same as quantity of water in liters falling per second).
Watts would be the amount of pressure water is exerting on an object at the bottom of the fall (like a boat or something) or how much power/work that water can give if it were to push the boat and make it move.
Volts would be the difference (in height) between the level of water at the top of the dam and the level of water at the bottom of the dam.

#### slow'puter

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Quote:
 Originally Posted by z_one If we were to compare electricity passing through a wire to the Niagara Falls... Amps would be how fast the water is falling down (same as quantity of water in liters falling per second). Watts would be the amount of pressure water is exerting on an object at the bottom of the fall (like a boat or something) or how much power/work that water can give if it were to push the boat and make it move. Volts would be the difference (in height) between the level of water at the top of the dam and the level of water at the bottom of the dam.
Bravo!

#### sccr64472

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Quote:
 Originally Posted by slow'puter Bravo!
Now explain to him in terms of AC and the difference between resistance and impedance

#### slow'puter

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Quote:
 Originally Posted by sccr64472 Now explain to him in terms of AC and the difference between resistance and impedance
That would be cruel.... It took me 2 tries to get it right back in college. Electricity is not my thing.

#### zone

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Quote:
 Originally Posted by slow'puter Bravo!
Thanks ! That's how someone explained it to me the first time.

Lol sccr.. You're mean dude !

The term impedance is a general expression which can be applied to any forum user who gets in the way of the flow of threads/posts on Overclock.net.
Thus this expression could be used to denote a resistance, a pure reactance, or as is most likely in the real world, a complex combination of both reactance and resistance to other people enjoying themselves and learning on this forum

#### cyrixMII300

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i think this might be simpler explanation if i migth try....

amp is like the gas in ur car....without ur gas the car doesnt run and without amps nothing runs...

R, resistance is the total weight of the car and the ppl in it, the bigger the car the more gas u will guzzle and the less efficient the car will be. Also the engine will suffer in performance since it has to work harder

P is the net amount of performance that is available for ur car in terms of the engine capacity. the bigger the cc of the engine the more performance u get and the easier u get over the load problem.

V is simply the constant of efficiency more or less...consider that when u drive the car at a certain speed u burn certain amount of fuel but there is always a point when u can drive the car at a faster speed and burn less fuel. this is the point of breakeven when the speed and the weight of the car together is able to guarantee lower consumption of fuel..for example drive the car at 70MPH u burn a gallon a mile; drive at 80MPH u burn 3/4 gallon per mile and drive at 90MPH u burn 1 1/2 gallon a mile...

consider also that most high tension power lines are high voltage meaning they are at least 11kV or higher depending on the country. The higher coltage is simply because you will more easily overcome resistance and lose less AMPs as a consequence...

hope it helped

as for impedance i agree with z one...it is accurate; impedance some1 who is intentionally a problem and resistance it is naturally occuring

#### sccr64472

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Amps is like gas in a car? I don't follow you there. Amperage is a speed rating.

#### cyrixMII300

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i wouldnt equate amps with speed rating....amps are what run electrical components..thats the juice....when we actually up the voltage for a cpu we are actually increasing the amount of amp available for the cpu to overcome the resistance that is inherent inside the cpu... because we cannot change the value of resistance inside the cpu, the only other thing to do to make it work harder is to increase the voltage based on the equation V=IR, the volts we supply divided by the R will give the amount of amps available...amps is the consumption of current that is required to run any electrical equipment thats y it is the gas...

edit: just to clear the points better and also to give a better definition to our friend mr.canada, plz follow the link;

http://www.wisegeek.com/what-is-amperage.htm

#### sufiankane

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Ok....i will give it my best shot. You have an electron. A wire has many electrons. When an electrons moves it has energy because it moves yes? It can slow down to give energy to a component. Now i can explain Amperage. Amperage is just how many electrons are passing a certain point in one second. More electrons pass a point means they must be moving faster. Must have more energy must have a higher current.

Now. Watts is just the energy used by a component in 1 second. Example. An example. a 7800GTX has a power of 250 watts. How much energy does it use in 1 minute. As i said watts=energy used in 1 second. therefore it uses 250J in one second. in 60 seconds it will use 60*250 = 15000.

Next is to explain the wonders of voltage. This is quite tricky. Voltage is the energy that 1 unit of charge has. Really...as i said before amperage is the speed at which an electorn moves and so on with energy. Well i lied. Voltage is how much energy 1 couloumb of charge has. And an electron has a charge of something very small. So....voltage is just a measure of how much energy an electron has got. When this moves through a component it transfers its energy to the component.

Now to link this. Basically....for a component at CONSTANT TEMPERATURE r=v/I. where r is the resistence and I is the current and V is the voltage. Now a question again.

A computer fan has a voltage of 12V and a current of 0.1A. what is the resistence. r=12/0.1=120 ohms. ohms is the unit for resistence.

Another thing this is used for is finding power. P=IV

Now you can say a lightbulb has a current of 0.1A and a voltage of 1000V. what is the power? 0.1*1000=100W

Unfortunately i have to go to bed tired. I promise how to link all of his together and if you do notunderstand anyhting just ask i am happy to help. As well as make and mark questions. i will write the rest tomorrow as in why P=IV works and many tiher things and a better explanation of voltage.

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I appreciate your effort, but it was kind of confusing. I understand the basics though because of Cyrix and his WiseGEEKS link though.

Now, if I'm correct so far, it goes like this:

Say we're talking about a river with a dam at the end. The river represents the wire, the dam represents the technology that slows down or makes the electricity smaller (still not clear on which is used, when), and on the other side of the dam is the appliance that needs a certain amount of electricity.

Now say at a certain height on the banks of the river (wire) is the maximum safe amount of water (amps) that can be carried through the river (wire). The speed in which water (amps) can travel because of the maximum potential water (amps) that the river (wire) can hold is volts, right? Amperage is the actual amount of water that is flowing through the river, maximum or not. At the dam, the dam (or circuit break/resistor/capacitor/whatever) technology filters the water (amps) down to smaller, safer amounts for the appliance that needs it.
Watts is just the total energy being used; Amps (amount of energy) X Volts (speed in a sense) = Watts.

That much is clear to me if I'm correct, but I'd like if someone would correct me if I'm wrong, and/or elaborate more on how it works.

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Oops, lagged and double posted. Sorry.

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I hate to triple post, but... anyone?

#### dpg

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Electricity

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Thanks for the gigantor read. I was just wondering mostly about my analogy and if could pass as "correct" in a way lol

#### Dngrsone

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The anlogy the works best in my experience is slightly different for the Niagara falls model--

If we are equating electricity to plumbing, then the conductor (wire) would be a water pipe. Current (measured in amps) is the water flowing through the pipe-- the faster the water flows, the more current there is. Voltage would be water pressure-- even if there is no current there is still the potential there (the pressure) and the more pressure (voltage) the more current you'll get when it is allowed to flow.

Resistance is just that, it impedes the flow of current, maybe through a valve, or a constriction in the pipe-- there are a number of ways to do so in both plumbing and electricity.

Power in this analogy could be expressed roughly as the volume of water handled.

Now here's a tidbit that eludes a lot of people when they start talking electrical flow-- using the electron theory of flow, electrons come from the negative side of the DC power source, flow through the circuit and eventually end up at the positive side. Well and fine. What people trip over is the though that when one closes a switch, say, and completes the circuit, a whole pile of electrons flood out of the power source. That is not quite right.

Just as the pipes supplying water to your home are not empty of water when the valves are closed, the wires are not empty of electrons-- they are in every atom of every molecule in the wire (and everything else- it just so happens that they are more easily moved from their place in metal atoms to accommodate current flow), so closing the circuit results in nearly instantaneous current flow.

Ohm's law I=E/R
Power equation P=I*E

Where

I = Current in amps
E = Voltage in volts
R = Resistance in ohms
P = Power in watts

Does that help?