# physics

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A certain copper wire has a resistance of 12.0 \Omega.At what point along its length must the wire be cut so that the resistance of one piece is 5.0 times the resistance of the other?

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resistance is proportional to length, so the lengths have to be in the ratio of 1:4, so the cut must be at 1/5 the length, giving you lengths of 1/5 and 4/5 the length. Actual resistances are 10/5 ohms and 40/5 ohms, or R1=2 ohms and R2=8

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