Home
Class 12
PHYSICS
A copper wire of cross-sectional area 1 ...

A copper wire of cross-sectional area `1 mm^2` carries a current of 0.21A Find the drift velocity of free electrons. Given density of free electrons in copper `=8.84 times 10^(24)m^-3` and electronic charge `e=1.6 times 10^-19 C`.

Text Solution

Verified by Experts

Current in copper wire `I=0.21A` electronic charge `e=1.6 times 10^(-19)C`, density of free electrons in copper `n=8.84 times 10^(24)m^-3` , cross sectional area of copper wire `A=1mm^2=10^-6m^2`
`therefore` Drift velocity
`v_d=1/(n eA)=0.21/((8.84times10^24)times(1.6times10^-19)times10^-6)`
`=0.148m.s^-1`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    CHHAYA PUBLICATION|Exercise HIGHER ORDER THINKING SKILL (HOTS) QUESTION|26 Videos
  • CURRENT ELECTRICITY

    CHHAYA PUBLICATION|Exercise NCERT TEXTBOOK QUESTION WITH ANSWER HINT|4 Videos
  • COMMUNICATION STSTEM

    CHHAYA PUBLICATION|Exercise CBSE SCANNER|28 Videos
  • DIFFRACTION AND POLARISATION OF LIGHT

    CHHAYA PUBLICATION|Exercise CBSE SCANNER|27 Videos

Similar Questions

Explore conceptually related problems

A Cu wire of cross sectional area 1mm^2 is carying current 0.21A. What is the drift velocity of the free ejectrons in the wire?. Electron density of Cu = 8.4xx10^28/m^3 .

Estimate the average drift speed of conduction electrons in a copper wire of cross sectional area 1.0 times 10^-7 m^2 carrying a current of 1.5 A.Assume that the number density of conduction electrons is 9 times 10^25 m^-3 charge of an electron = -1.6 times 10^-19C .

Knowledge Check

  • When a current of 1 A flows through a copper wire of cross sectional area 1mm^2 the drift velocity of free electrons becomes v, What will be the drift velocity of free electrons when the same current flows through a copper wire of cross sectional area 2mm^2 ?

    A
    `v/2`
    B
    v
    C
    2v
    D
    4v
  • Similar Questions

    Explore conceptually related problems

    Estimate the average drift speed of conduction electrons in a copper wire of cross sectional area 1 times 10^-7 m^2 carrying a current of 1.5 A.Assume that each copper atom contributes one conduction electron. The density of copper is 9 times 10^3 kg.m^-3 and its atomic mass is 63.5 u .

    The number of free electrons per unit volume in a metallic conductor is 10^22 cm^-3 .The area of cross section of the conductor is 1mm^2 and the strength of current through the conductor is 1A. Determine the drift velocity of the free electrons,(Given that the charge of an electron -1.6 times 10^-19 C )

    Estimate the average drift speed of conduction electrons in a copper wire of cross-sectioal area 1.0xx10^(-7)m^2 carrying a current of 1.5 A. Assume that each copper atom contributes roughly one conduction electron. The density of copper is 9.0xx 10^3 kg//m^3 and its atomic mass is 63.5.

    (a) Esttimate the average drift speed of conduction electrons in a copper wite of cross-secttonal area 1.0 xx 10 ^(-7)m^(2) carrying a current of 1.5A. Assume the each copper atom contrbutes roughly one conduction electron. The density of copper is 9.0 xx 10 ^(3)kg//m^(3), and its atomic mass is 63.5 u. (b) Compare the drift speed obyained above with, (1) thermal speeds of copper atoms at ordinary temperaturtes. (ii) speed of propagation of electric field along the conductor which causes the drift motion.

    A copper wire of diameter 2/(3sqrtpi)mm is carrying a current of 1 amp. Calculate the number of free electrons which flow past any cross section of the wire per sec Also find the average speed with which free electrons are flowing in the copper wire assuming that there is one free electron per atom of copper. Number of atmos per cm^3 of copper =9 times 10^22 , electronic charge =1.6 times 10^-19 coulomb.

    Obtain an expression showing the relation between the current-density j in a current-carrying conductor, the drift velocity v_d , the number of free electrons per unit volume n and the electronic charge e.

    A conductor of uniform cross-section is carrying a current of 1 ampere. The number of free electrons flowing across the cross section of the conductor per second is