Question

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.

A

b.

B

c.

C

d.

D

Answer: (b).B

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Q. 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

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