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A straight conductor of uniform cross-se...

A straight conductor of uniform cross-section carries a current `I`. Let `s=` specific charge of an electron. The momentum of all the free electrons per unit length of the conductor, due to their drift velocity only, is

A

`I s`

B

`sqrt(I//s)`

C

`I//s`

D

`(I//s)^2`

Text Solution

Verified by Experts

The correct Answer is:
C
`I = n A e v_d` or `v_d = (I)/( n Ae)`
Total number of free electrons in the unit length of conductor, `N = n A xx 1`.
Total linear momentum of all the free electrons per unit length `= ( N m ) v_d = n A m xx (I)/( n A e) =( I )/( ( e//m) ) = ( I )/( s)`
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Knowledge Check

  • In a straight conductor of uniform cross-section charege q is flowing for time t. Let s be the specific charge of an electron. The momentum of all the free electrons per unit length of the free electrons per unit length of the conductor, due to their drift velocity only is

    A
    `(q)/(ts)`
    B
    `((q)/(ts))^(2)`
    C
    `sqrt((q)/(ts))`
    D
    `qts`

  • Drift velocity of free electrons when current passes through the conductor is of the order of

    A
    `10 mm//s`
    B
    `10 m//s`
    C
    `10 km//s`
    D
    `10^(6) m//s`

  • A straight conductor of uniform cross section carries a time varying current, which varies at the rate dI//dt = I. If s is the specific charge that is carried by each charge carries of the conductor and l is the length of the condcutor, then the totalt force experienced by all the charge carries per unit length of the conductor due to their drift velocities only is

    A
    `F = I s`
    B
    `F = (I)/(2sqrtls)`
    C
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    D
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