A metallic wire has a diameter of 4.12 mm. When the current in the wire is 8 A, the drift velocity is 5.4*10^-5 m/s.(adsbygoogle = window.adsbygoogle || []).push({});

What is the density of free electrons in the metal?

I have considered a wire of cross-sectional area A, with current I. V is the drift velocity of the free charges in the conductor and n is the number of charged particles per unit volume. Then the current is given by I = nqva, where q is the magnitude of the charge on a charge carrier.

I = 8

n = density??

A = (2.06)^2 * 3.14

v = 5.4 x 10^-5

q = ??

I am unsure of how to finish the problem. We are looking for n. But what is q? Are all my other numbers correct?

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