(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Here's the problem.

The resistance of a piece of constantan wire of radius 0.6mm is reduced to 1/3 its original resistance when a unifrom layer of copper is deposited on it. Find the thickness of the layer of copper

(Resistivity of constantan = 49*10^-8 ohm m

resistivity of copper =1.7*10^-8 ohm m

2. Relevant equations

I do think that it is related to

R =pl/A where p is the resistivity , l = length of wire

A = cross-section area

3. The attempt at a solution

I've tried ... but don't know how to work out

...

Thanks

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# Physics - resistivity

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