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Question
If the charge on an electron is 1.6 × 10−19 coulombs, how many electrons should pass through a conductor in 1 second to constitute 1 ampere current?
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Solution
Given:
Current,/=1A
Time,t=1s
Using the formula:
`I=Q/t`
or,
`Q=Ixxt `
=`1xx1`
=1=C
Now, if the charge is `1.6xx10^-19`C, the number of electrons is 1.So, if the charge is 1C, the number of electrons is given by:
`1/(1.6xx10^-19)xx1=6.25xx10^18`
Thus, `6.25xx10^18`electrons should pass though a conductor in 1 second to constitute 1 ampere current.
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