A uniform wire long of resistance and cross-sectional area is connected to a battery…

PHYSICS · Single correct · CBSE · Physics · Current Electricity · Current Electricity

Problem

A uniform wire

1.5\,\text{m}

long of resistance

0.30\,\Omega

and cross-sectional area

1.0\,\text{mm}^2

is connected to a

3.0\,\text{V}

battery of negligible internal resistance. The free-electron number density in the wire is

9.0\times10^{28}\,\text{m}^{-3}

; take

e=1.6\times10^{-19}\,\text{C}

. The electron mobility in the wire is closest to (a)

7.0\times10^{-4}\,\text{m}^2\,\text{V}^{-1}\,\text{s}^{-1}

(b)

3.5\times10^{-4}\,\text{m}^2\,\text{V}^{-1}\,\text{s}^{-1}

(c)

1.8\times10^{-4}\,\text{m}^2\,\text{V}^{-1}\,\text{s}^{-1}

(d)

3.5\times10^{-5}\,\text{m}^2\,\text{V}^{-1}\,\text{s}^{-1}