A specimen of metal has n valence electrons per m3. If vx is the avera – McqOptions

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1.	A specimen of metal has n valence electrons per m3. If vx is the average velocity of these electrons, each having a charge e, the current density J is
A.	J = ne vx
B.	J = - ne vx
C.	J =
D.	J =
Answer» C. J =

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