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| [[File:lighterstill.jpg]][[File:Short-circuit1.jpg|right|frame]] | | [[File:lighterstill.jpg]][[File:Short-circuit1.jpg|right|frame]] |
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− | *[http://en.wikipedia.org/wiki/19th_century 1854] | + | *[https://en.wikipedia.org/wiki/19th_century 1854] |
| ==Definition== | | ==Definition== |
− | *1:an abnormal low-[http://en.wikipedia.org/wiki/Electrical_resistance resistance] connection between two nodes of an [http://en.wikipedia.org/wiki/Electrical_circuit electrical circuit] intended to be at different voltages. This results in an excessive [http://en.wikipedia.org/wiki/Electric_current electric current] (overcurrent) limited only by the [http://en.wikipedia.org/wiki/Th%C3%A9venin%27s_theorem Thévenin equivalent resistance] of the rest of the network and potentially causes circuit damage, overheating, [[fire]] or [[explosion]]. Although usually the result of a fault, there are cases where short circuits are caused intentionally, for example, for the purpose of voltage-sensing [http://en.wikipedia.org/wiki/Crowbar_(circuit) crowbar circuit protectors]. | + | *1:an abnormal low-[https://en.wikipedia.org/wiki/Electrical_resistance resistance] connection between two nodes of an [https://en.wikipedia.org/wiki/Electrical_circuit electrical circuit] intended to be at different voltages. This results in an excessive [https://en.wikipedia.org/wiki/Electric_current electric current] (overcurrent) limited only by the [https://en.wikipedia.org/wiki/Th%C3%A9venin%27s_theorem Thévenin equivalent resistance] of the rest of the network and potentially causes circuit damage, overheating, [[fire]] or [[explosion]]. Although usually the result of a fault, there are cases where short circuits are caused intentionally, for example, for the purpose of voltage-sensing [https://en.wikipedia.org/wiki/Crowbar_(circuit) crowbar circuit protectors]. |
| ==Description== | | ==Description== |
− | A '''short circuit''' (sometimes abbreviated to short or s/c) is an [http://en.wikipedia.org/wiki/Electrical_network electrical circuit] that allows a current to travel along an unintended [[path]], often where essentially no (or a very low) [http://en.wikipedia.org/wiki/Electrical_impedance electrical impedance] is encountered. The electrical [[opposite]] of a short circuit is an "[http://en.wikipedia.org/wiki/Open-circuit_voltage open circuit]", which is an infinite resistance between two nodes. It is common to misuse "short circuit" to describe any [[electrical]] malfunction, regardless of the actual [[problem]]. | + | A '''short circuit''' (sometimes abbreviated to short or s/c) is an [https://en.wikipedia.org/wiki/Electrical_network electrical circuit] that allows a current to travel along an unintended [[path]], often where essentially no (or a very low) [https://en.wikipedia.org/wiki/Electrical_impedance electrical impedance] is encountered. The electrical [[opposite]] of a short circuit is an "[https://en.wikipedia.org/wiki/Open-circuit_voltage open circuit]", which is an infinite resistance between two nodes. It is common to misuse "short circuit" to describe any [[electrical]] malfunction, regardless of the actual [[problem]]. |
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− | A common type of short circuit occurs when the positive and negative terminals of a [http://en.wikipedia.org/wiki/Battery_(electricity) battery] are connected with a low-[http://en.wikipedia.org/wiki/Electrical_resistance resistance] conductor, like a wire. With low resistance in the connection, a high [http://en.wikipedia.org/wiki/Current_(electricity) current] exists, causing the cell to deliver a large amount of energy in a short time. | + | A common type of short circuit occurs when the positive and negative terminals of a [https://en.wikipedia.org/wiki/Battery_(electricity) battery] are connected with a low-[https://en.wikipedia.org/wiki/Electrical_resistance resistance] conductor, like a wire. With low resistance in the connection, a high [https://en.wikipedia.org/wiki/Current_(electricity) current] exists, causing the cell to deliver a large amount of energy in a short time. |
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− | A large current through a battery can cause the rapid buildup of [[heat]], potentially resulting in an [[explosion]] or the release of hydrogen gas and [http://en.wikipedia.org/wiki/Electrolyte electrolyte] (an acid or a base), which can burn tissue, cause [[blindness]] or even [[death]]. Overloaded wires can also overheat, sometimes causing damage to the wire's [[insulation]], or a [[fire]]. High current conditions may also occur with [http://en.wikipedia.org/wiki/Electric_motor electric motor] loads under stalled conditions, such as when the impeller of an electrically driven pump is jammed by debris; this is not a short, though it may have some similar [[effects]]. | + | A large current through a battery can cause the rapid buildup of [[heat]], potentially resulting in an [[explosion]] or the release of hydrogen gas and [https://en.wikipedia.org/wiki/Electrolyte electrolyte] (an acid or a base), which can burn tissue, cause [[blindness]] or even [[death]]. Overloaded wires can also overheat, sometimes causing damage to the wire's [[insulation]], or a [[fire]]. High current conditions may also occur with [https://en.wikipedia.org/wiki/Electric_motor electric motor] loads under stalled conditions, such as when the impeller of an electrically driven pump is jammed by debris; this is not a short, though it may have some similar [[effects]]. |
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| In electrical devices, unintentional short circuits are usually caused when a wire's [[insulation]] breaks down, or when another conducting material is introduced, allowing charge to [[flow]] along a different [[path]] than the one intended. | | In electrical devices, unintentional short circuits are usually caused when a wire's [[insulation]] breaks down, or when another conducting material is introduced, allowing charge to [[flow]] along a different [[path]] than the one intended. |
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− | A short circuit may lead to formation of an [http://en.wikipedia.org/wiki/Electric_arc arc]. The arc, a channel of hot ionized [http://en.wikipedia.org/wiki/Plasma_(physics) plasma], is highly conductive and can [[persist]] even after significant amount of original material of the conductors was evaporated. Surface erosion is a typical sign of electric arc damage. Even short arcs can remove significant amount of materials from the electrodes.[http://en.wikipedia.org/wiki/Short_circuit] | + | A short circuit may lead to formation of an [https://en.wikipedia.org/wiki/Electric_arc arc]. The arc, a channel of hot ionized [https://en.wikipedia.org/wiki/Plasma_(physics) plasma], is highly conductive and can [[persist]] even after significant amount of original material of the conductors was evaporated. Surface erosion is a typical sign of electric arc damage. Even short arcs can remove significant amount of materials from the electrodes.[https://en.wikipedia.org/wiki/Short_circuit] |
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| [[Category: Physics]] | | [[Category: Physics]] |