AP Physics

A certain length of wire has a resistance of 21 ohms. This wire is melted down and from the same volume of material a new wire is formed that is three times longer than the original wire. What is the resistance of a new wire?

***PLEASE SHOW ALL WORK!!!

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  1. Area L = volume
    so if 3 times longer, then 1/3 the area
    3 * 21 = 63 ohms

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