How does the length of wire affect resistance. Please explain well [while being scientific].
2007-01-22 07:23:59 · 7 answers · asked by mbchelsea 1 in Science & Mathematics ➔ Physics
When you have a long wire, the electrons have to squeeze together for longer to be able to pass through the wire than they do in order to be able to pass through a short wire
2007-01-23 07:09:50 · answer #1 · answered by paula m 1 · 0⤊ 0⤋
In most LRC circuits, the resistance of the wire is negligible compared to the rest of the circuit. There are certain cases, however, where the wire is so long that the resistance of the wire has to be considered. For example, power lines often must travel hundreds of miles to reach their destination. With wires this long, the internal resistance of the wire can no longer be ignored. (I believe in such cases a transformer is used to increase the voltage and decrease the current in the wire, but I could be wrong.)
In any case, imagine a long wire. Let's say that the internal resistance of the wire is such that each meter of wire has an internal resistance of approximately 10 milliohms. Every subsequent meter of wire is like adding another 10-milliohm resistor in series. The equivalent resistance then becomes the summation of the internal resistance of each meter of wire.
R(equivalent) = R1 + R2... = 10 millohm + 10 milliohm...
2007-01-22 15:33:46 · answer #2 · answered by ybdogsct 2 · 0⤊ 0⤋
Proportional. For any given wire, twice the length means twice the resistance. Wire tables give resistance per unit length.
2007-01-22 15:31:37 · answer #3 · answered by Anonymous · 0⤊ 0⤋
For the same cross section, the resistance goes up linearly as the length. Resistance = resistivity x (length / area)
2007-01-22 15:27:26 · answer #4 · answered by Gene 7 · 1⤊ 0⤋
a wire's resistance is directly proportional to its length.
eg
R = kL (typical "formula" relating length and resistance)
R is resistance in ohms
L is length in centimeters
k is coefficient in "ohms/cm"
2007-01-22 15:26:33 · answer #5 · answered by atheistforthebirthofjesus 6 · 0⤊ 0⤋
It goes like this:
-the longer a wire is the more time required by charge (electron) to flow from one end to another
-more time, means current is lesser (I = Q/t; t is larger for same Q)
-lesser current flowing means greater reistance of charge
2007-01-23 01:02:15 · answer #6 · answered by guyfromthesky 2 · 0⤊ 0⤋
its like 2 Ohms per 100 feet I think
less for thiick wires
2007-01-22 15:27:53 · answer #7 · answered by kurticus1024 7 · 0⤊ 0⤋