Why does the resistance of a metallic conductor increases with the length of a wire?
2007-03-15 06:20:03 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Longer wire means the electrons have a longer way to travel, so it's harder for them. They bump into more stuff on the way and lose more of their energy.
Imagine you had to travel through a tunnel filled with people. What's easier--long tunnel or short tunnel?
To put it more mathematically, resistors add in series. Longer wire is like adding more resistance in series. Hence, the resistance is proportional to the length.
Edit--answer below got the last point backwards--fat wires have less resistance (use the tunnel analogy to see why this is obvious)
2007-03-15 06:24:04 · answer #1 · answered by Anonymous · 0⤊ 0⤋
This is depending upon the purity of the conductor. If it is Copper less, and if it is Gold it is further less and so on.
Also it is directly proportionate to the dia. of the conductor.
So we use very thin wire to have the least resistance.
2007-03-15 13:24:13 · answer #2 · answered by tnkumar1 4 · 0⤊ 1⤋
There's more of the metal for the electrons to push through so it's more difficult flor the electrons to flow.
2007-03-15 13:22:56 · answer #3 · answered by Gene 7 · 1⤊ 0⤋