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There is indeed current. You just need to rearrange your formula to V/R = I to find the amount of current. Since you are basically dividing by zero (R), the value of I is infinite not zero.

hello

Here is another basic questions.I would to know why does a battery create sparks when you take a wire and touch the negative of a battery with the positive.? Also why is it said there are no current? V = I * R is the basic formula, with a negligable resistance in the wire and lets say a 12 volt fully charge car battery. With no resistance, there can be no current? but if there is no current, why is there sparks. The voltage in this case is only a potential.

thanks ken

Says who?

No. With a very low resistance, you will have a very large current - turning the Ohm's Law equation around to solve for current, you get I = E/R. For a 12 volt battery, and a foot of #12 wire (1.65 ohms/1000 ft), you get I = 12/.00165 = 7273 amps!!

There is Lotsa current, therefore Lotsa sparks.

Sparks are caused by heat (incandescence). Hot metal gives off light and so does hot, ionized gas.

So why does it create sparks?? and not when you put a resistor or a small load. I guess when the positive meet negative, the holes and electron join together, why should there be sparks ? Is there en electron overload? if so how and why

Ken

No, I didn't say that. The current is the same at all points in a series circuit.

When you touch the wire to the battery terminal, you briefly make a very small-area connection. The battery tries to force a large current through that connection, so the wire at that point heats to incandescence. Also, if you jiggle the wire to make and break the connection, the current will try to keep flowing after you break the connection, making a small arc.

Well, the battery does have some internal resistance, but I don't think we can make any estimate of its value from this experiment.

Ok so what you are saying is the battery is able to give it off but not able to receive it at the same rate! So the internal resistance of the battery is therefore much higher then the wire, correct?

Ken

This may be sci.electronics.misc but your question should be in sci.electronics.basics and in fact it so basic that you should either read a lot or go to

Thanks for the web site ken

Ken,

I'm not sure I totally understand your question but there can only be sparks or arcs if there is current flow. It comes from the inductance in the wire which when the current is interrupted by making an breaking the connection generates very high voltages, enough to cause arcing much like what occurs in a relay.

Tom, P.E.