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The number of free electrons per 100 mm ...

The number of free electrons per 100 mm of ordinary copper wire is `2xx10^(21)`. The average drift speed of electorn is `0.25 mm//s`. What is the current flowing?

A

0.8A

B

8A

C

80A

D

5A

Text Solution

Verified by Experts

The correct Answer is:
2
No. of electron per unit volume
`n=(2xx10^(21))/(10xx10 ^(-3)xxA)`, here A=cross section area
`I="ne"Av_(d)` solvet it.
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