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A copper wire carries a current of densi...

A copper wire carries a current of density j. We assume that one free electron (Charge = e, number density =n) corresponds to each copper atom. Here v is the mean velocity of thermal motion of an electron. Then :

A

a)the drift velocity of electrons is `(j/"ne")`

B

b)the time required to cover displacement I is `l/v_d`

C

c)the time required to cover displacement I is `(("nel")/j)`

D

d)the distance actually travelled corresponding to displacement I by electrons is `(("nelv")/j)`

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The correct Answer is:
A, B, D
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