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How would Voltage & Current relate to a garden hose? I know that the pressure of the hose is Voltage and the flow of the hose is current but I need more details about it.
No, you can't. Voltage is a pressure and is directly analagous to mechanical pressure. This is not an uncommon analogy for a teaching aid because it is exactly the same mathematically: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir.htmlYou can think of voltage as the amoutn of energy to move an electron through a resistance
No, you can't. Voltage is a pressure and is directly analagous to mechanical pressure. This is not an uncommon analogy for a teaching aid: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/watcir.html
As you can see:
pressure = voltage
volume flow rate = amperage
resistance = resistance
Who?He's correct.
I suppose that is a rhetorical question, but it is often very useful to cross back and forth between mechanical and electrical energy. It may not be as direct, but I use the concept regularly when figuring out things like fan or pump efficiency or cross-checking electrical and mechanical energy via efficiency: a joule of pump energy and a joule of electrical energy are the same thing and you can go backwards all the way from flow rate and pressure to kw and voltage and amperage.What are the units of a volt?
Then again, why do we need to make an analogy between electricity and water systems. Its totally useless. It was never worth a damn for anything other than showing there was an analogy.
Maybe not, but I've seen the analogy taught in both directions in school. For people who can't understand one, relating it to the other, if only for 15 minutes when first learning it, can be helpful.I never did a single circuit problem saying, soooo if I think of the pressure through the inductor..............![]()
Agnostic said:You can think of voltage as the amoutn of energy to move an electron through a resistance
and current as how many electrons are moving through the resistance.
I suppose that is a rhetorical question, but it is often very useful to cross back and forth between mechanical and electrical energy. It may not be as direct, but I use the concept regularly when figuring out things like fan or pump efficiency or cross-checking electrical and mechanical energy via efficiency: a joule of pump energy and a joule of electrical energy are the same thing and you can go backwards all the way from flow rate and pressure to kw and voltage and amperage.
This analogy business is not necessary. [..] I dont need to know anything about pumps, water, or pressure to understand whats going on, and I avoid falling into traps by drawing too close an analogy with mechanical systems. Electrons dont have turbulence, water flow in pipes do, this is the danger of analogies.
I dont understand why people cant just accept voltage, current, and resistance for what it is. Like I said, you apply a voltage to a resistor, and you get a current. Cause leads to effect. There is no need for any analogies here. These are the physical observations of the system. I dont have to go through analogies just to explain what I am seeing before my own eyes.
You dont need an analogy for water systems, you accepted that for what it was. Similarly, you should accept voltage, current and resistance for what it is. There is a difference in potential. The charge moves in response to that change in potential. You get current. It is what it is.
So, current, for an inductor, LAGS behind voltage since sint lags behind cost by 90......the opposite holds for a capacitor.
What do you mean one does not cause the other?
Get a battery, plug the ends onto a resistor. You will get a flow of current through the resistor.
You just applied a voltage to the resistor. The effect is you see a current. What does phase have to do with anything? I never said an AC source.
Ok it lags, fine. Does that mean you get a current before you applied a voltage to the system?
No, its not.
You mean to tell me, you cant decide if you pluged in your circuit to a voltage supply, or it magically ran current through itself?
You *had* to plug it in at some point in time.
Charge simply wont move if there is no potential difference.
MY point was voltage does not always CAUSE current.
I dont understand why people cant just accept voltage, current, and resistance for what it is. Like I said, you apply a voltage to a resistor, and you get a current. Cause leads to effect. There is no need for any analogies here. These are the physical observations of the system. I dont have to go through analogies just to explain what I am seeing before my own eyes.
You dont need an analogy for water systems, you accepted that for what it was. Similarly, you should accept voltage, current and resistance for what it is. There is a difference in potential. The charge moves in response to that change in potential. You get current. It is what it is.
True of course.The trouble with analogies is that they are only partially equivalent. A current in a wire is surrounded by a magnetic field. If the field is time changing, & another circuit is in proximity, induction takes place. Fluid flow does not exhibit this "transformer behavior".