If a current of 300 mA is following in a conductor, then the no.of electrons passed through the conductor in 4 min is (charge on an electron `=1 . 6 xx 10^(-19) C`

Options

A. `4 . 5 xx 10^(20)`
B. `9 . 0 xx 10^(20)`
C. `4 . 5 xx 10^(18)`
D. `9 . 0 xx 10^(18)`

Answer

A

Explanation

Given :
Current (I) = 300 mA = 0.34
Time (t) = 4 min = 240 s and charge on an electron
`(e) = 1.6 xx 10^(-19)` C
We know that charge passing through a conductor
`(q) = I xx t = 0. 3 xx 240 = 72 ` C
Therefor no. of electrons passed through the conductor
`(n) = (q)/(e) = (72)/(1.6xx10^(-19)) = 4. 5 xx 10 ^(20)`