Question

When 5 V potential difference is applied across a wire of length 0.1 m, the drift speed of electrons is `2.5 xx 10^(-4) ms ^(-1)`. If the electron density in the wire is ` 8 xx 10^(28) m^(-3)`, the resistivity of the material is close to :
A. `1.6xx10^(-8)Omegam`
B. `1.6xx10^(-7)Omegam`
C. `1.6xx10^(-6)Omegam`
D. `1.6xx10^(-5)Omegam`

Answer 1

Correct Answer - D
`R=(rhol)/(A)`
`(V)/(i)=(rhol)/(A)implies(V)/(nAeV_(d))=(rhol)/(A)impliesrho=(V)/(n eV_(d)l)`