Which one of the following expressions gives the current density in a conductor in…

PHYSICS · Single correct · CBSE · Physics · Current Electricity · Current Electricity

Problem

Which one of the following expressions gives the current density

J

in a conductor in terms of the number density of charge carriers

n

, elementary charge

e

and drift velocity

v_d

? (a)

\dfrac{1}{2}\,n e v_d

(b)

n e v_d

(c)

2 n e v_d

(d)

\dfrac{n e v_d}{\sqrt{2}}