A 1-mile long copper wire has a resistence of 10 ohms. Whats will be its new resistence when it is shortened by cutting it in half and doubling it over and using it as if it were one wire of half the length but twice the cross sectional area?"
2007-03-06 04:57:30 · 5 answers · asked by Melissa H 1 in Science & Mathematics ➔ Engineering
1/2 the length gives 5 Ohms
Two 5-Ohm resistors in parallel gives 2.5 Ohms
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2007-03-06 05:01:48 · answer #1 · answered by tlbs101 7 · 1⤊ 1⤋
10 Ohms
2016-12-18 07:25:45 · answer #2 · answered by ? 4 · 0⤊ 0⤋
It would be 2.5 ohms. Cutting length in half halves the resistance. Doubling the wires cross sectional area halves the resistance again. So you are at a quarter of the original 10 ohms and that is 2.5 ohms.
2007-03-06 05:13:36 · answer #3 · answered by Rich Z 7 · 2⤊ 1⤋
2.5 Ohms.
2007-03-06 05:55:47 · answer #4 · answered by Anonymous · 0⤊ 1⤋
5 ohms. You can get it by calculating 'resistance in parallel'.
2007-03-06 05:03:22 · answer #5 · answered by Anonymous · 1⤊ 2⤋