Ohms equal resitence, the more ohms a conducter has, the more electric current it resists. Can there be an electric conducter that resists no current?
2007-05-18 08:28:44 · 8 answers · asked by joe f 1 in Science & Mathematics ➔ Engineering
Yes, it's called a superconductor. Currently, they can only be made at extremely cold temperatures.
2007-05-18 08:32:56 · answer #1 · answered by Mark 3 · 0⤊ 0⤋
As above, yes, superconductors exhibit no resistance whatsoever. However, that does not mean that you can put infinite current through a superconductor. There is a point, a critical maximum current (the term escapes me at the moment) at which any superconductor suddenly goes resistive.
And to be proper, let's rephrase you statement and second question properly -
"Ohms is a unit of resistance, the more ohms of resistance a conductor has, the more IT RESISTS ELECTRIC CURRENT. Can there be a conductor with zero resistance?" (answer: yes) or maybe "...Can there be a conductor that does not resist any current?" (answer: no, no known superconductor remains superconducting for all currents)
2007-05-18 10:39:23 · answer #2 · answered by Gary H 6 · 0⤊ 0⤋
What Ohm stated is resistance is the ratio of voltage(drop) for a given current. If the voltage does not drop across a device then the resistance is defined as zero. And, if the voltage should increase, the drop is negative and so is the resistance. Electronic engineers regularly deal with situations that have both zero and negative resistance. A virtual ground is an example of zero resistance in a common op amp. A circuit element that can absorb energy from outside the connected circuit (radio antenna) is treated as a negative resistance. No special exotic super conductors required.
your question is probably directed at the concept of moving energy through wires without suffering any loss and as a practical matter, that is an unreasonable expectation.
2007-05-18 09:12:41 · answer #3 · answered by lare 7 · 0⤊ 1⤋
Yes they are know as super conductors. They have a negative resistance when they are very cold. Once i start the current flowing and short across the inductor the current will flow forever unless u allow it to heat up.
2007-05-18 10:52:06 · answer #4 · answered by JOHNNIE B 7 · 0⤊ 0⤋
No. everything, good or poor conductor has resistance to the flow of its molecules, you can have excellent conductors with very little resistance and these are usually the "precious" metals - pltignum, gold, silver etc
2007-05-18 08:36:02 · answer #5 · answered by Adrian G 5 · 0⤊ 1⤋
Focused light.
2007-05-18 12:07:54 · answer #6 · answered by poppy_41 1 · 0⤊ 1⤋
dilute sulfuric asid
2007-05-18 08:33:17 · answer #7 · answered by Tuncay U 6 · 0⤊ 1⤋
superconductors
2007-05-18 08:33:33 · answer #8 · answered by Anonymous · 0⤊ 0⤋