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Question
A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross section of the filament in 16 seconds would be roughly
Options
1020
1016
1018
1023
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Solution
1020
Explanation -
Current, i = 1A
Time, t = 16s
`"i" = "q"/"t"`
`"q" = "i" xx "t"`
q = 1 × 16
q = 16 C
Now,
q = n × e
where, n is number of electrons lost or gained
e = charge on 1 electron (1.6 × 10-19 C)
`"n" = "q"/"e"`
`n = 16/(1.6 xx 10^(-19))`
n = 1020
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