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प्रश्न
Estimate the average drift speed of conduction electrons in a copper wire of cross-sectional area 2.5 × 10−7 m2 carrying a current of 1.8 A. Assume the density of conduction electrons to be 9 × 1028 m−3.
उत्तर
We know that drift velocity, `V_d=1/(nAq)`
I is the current, n is charge density, q is charge of electron and A is cross-section area.
`:.V_d=1.8/(9xx10^28xx2.5xx10^(-7)xx1.6xx10^(-19))`
`V_d=5xx10^(-4) `
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संबंधित प्रश्न
Estimate the average drift speed of conduction electrons in a copper wire of cross-sectional area 2·5 × 10−7 m2 carrying a current of 2·7 A. Assume the density of conduction electrons to be 9 × 1028 m−3
(a) drift speed
(b) current density
(c) electric current
(d) electric field
On the basis of electron drift, derive an expression for resistivity of a conductor in terms of number density of free electrons and relaxation time. On what factors does resistivity of a conductor depend?
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(A) Free-electron density is different in different metals.
(B) Free-electron density in a metal depends on temperature.
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