This is a question from a TV game show. Fill the blank with appropriate words.
Current flowing through a wire is ... to the voltage drop across the wire.
The answer in the dots is "proportional".
I am wondering if this is really an accurate statement. Should it be "current flowing through a resistor..." instead?
Wire has inductance (no matter how small) because it produces a magnetic field and if the voltage is AC then the current will not be time-stamped proportional to voltage but somewhat lagging in time (depending on the frequency applied).
I am wondering if this is really an accurate statement. Should it be "current flowing through a resistor..." instead?
I'd prefer your version because it kind-of naturally excludes inductance being an effect.
Also, because there is no mention of wire length, transmission line effects can screw this simple TV game show answer completely.
Every wire has a resistor which increase with the length. Since it's very small, we normally ignore it. Thanks to Ohm law, we can calculate the dropping voltage due to a resistor : \$U = RI\$, \$I = U * \frac{1}{R}\$. As you can see, the current is proportional to the volage drop by a factor of \$\frac{1}{R}\$
As a wire has some resistance (ignoring superconducting conditions), I say that this is a fine answer. One volt is the amount of force required to move one ampere of current through one ohm of resistance. This would make the current proportional to voltage for a fixed resistance.
