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Question
A current of 3.2 mA flows through a conductor. If charge on an electron is −1.6 × 10-19 coulomb, find the number of electrons that will pass each second through the cross section of that conductor.
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Solution
Q = n × e,
C = 3.2 m A = 3.2 × 1000 A,
Q = −1.6 × 10−19
3.2 × 1000 = n × −1.6 × 10−19
n = `(3.2 × 1000)/(1.6 × 10^-19)`
n = `(3.2 × 10^-3)/(1.6 × 10^-19)`
= `2/(10^-16)`
n = 2 × 1016
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