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प्रश्न
4 × 1020 electrons flow through a circuit in 10 hours. Calculate magnitude of current. [1 e- = 1.6 × 10-19 C]
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उत्तर
Number of electrons = n = 4 × 1020
Time = t = 10 hours
t = 10 × 60 × 60 s
t = 36000 s
Charge on one electron = e = 1.6 × 10-19 C
Electric current = I = ?
Charge = Q = ne
Q = 4 × 1020 × 1.6 × 10-19
Q = 6.4 × 101
Q = 64 C
Electric current = I = `"Q"/"t"`
I = `64/36000 = 64/36 xx 10^-3"A"`
`= 16/9 xx 10^-3`
I = 1.77 × 10-3A
I = 1.77 mA
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