Current= voltage/resistance

[Dawson]

It is said that current equals voltage divided by resistance however in what instance is that true? A 9-volt battery gives off 2.7 amps I can make a generator that creates 27 volts but only gives off one amp in what way work? You can't tell me that 26 amps is being burnt off by 180 ft of 28 gauge wire. Especially since it is still in AC form at that point. Also the wall puts out 120 volts but only 15 to 20 amps. Can someone please explain.

 

[timhoward]

Electricity is just a flow of electrons, charged particles.

• Voltage is the difference in charge between two points.
• Current is the rate at which charge is flowing.
• Resistance is a material's tendency to resist the flow of charge (current).

(definitions stolen)

So to start again, a 9V battery doesn't "give off" 2.7 amps. You might connect a power hungry device to a 9V battery resulting in the charge having to move more quickly, said to be "drawing more current".

This web page might help:

Voltage, Current, Resistance, and Ohm's Law - learn.sparkfun.com

 

[Dawson]

Electricity is just a flow of electrons, charged particles.

• Voltage is the difference in charge between two points.
• Current is the rate at which charge is flowing.
• Resistance is a material's tendency to resist the flow of charge (current).

(definitions stolen)

So to start again, a 9V battery doesn't "give off" 2.7 amps. You might connect a power hungry device to a 9V battery resulting in the charge having to move more quickly, said to be "drawing more current".

This web page might help:

Voltage, Current, Resistance, and Ohm's Law - learn.sparkfun.com

I understand all of this but it still doesn't answer the question if I am creating 27 volts why is there not 27 amps what resistance is there and as far as pulling off a battery you can connect a 9-volt battery to something that requires way more than 2.7 amps but the 9-volt battery will not give off more than that. If you know any way to pull 9 amps off of a 9-volt battery or for that matter how to get 27 amps on my generator please let me know. But mostly I want to know where this so-called resistance is coming from, because it's not from The Wire.

 

[telectrix]

all wire has a resistance. the longer and thinner the wire, the greater the resistance.

 

[Julie.]

I understand all of this but it still doesn't answer the question if I am creating 27 volts why is there not 27 amps what resistance is there and as far as pulling off a battery you can connect a 9-volt battery to something that requires way more than 2.7 amps but the 9-volt battery will not give off more than that. If you know any way to pull 9 amps off of a 9-volt battery or for that matter how to get 27 amps on my generator please let me know. But mostly I want to know where this so-called resistance is coming from, because it's not from The Wire.

No, the resistance will be internally to the battery, plus any external resistance.

Similarly the generator will have internall resistance, plus in the case of a generator it has a special "resistance " called reactance, which is both inherant to the magnetic circuit inducing the voltage, and as a byproduct of changing current in a wire.

Proper generators have been designed carefully to reduce these effects, some random layout of conductors and magnets will more than likely have high values/effects .