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Current Electricity

JEE Main level, single correct, medium

30 of 380

Question 30 of 380

A current of $5A$ passes through a copper conductor (resistivity $=1.7\times {10}^{-8}\Omega m$ ) of radius of cross-section $5mm$ . Find the mobility of the charges if their drift velocity is $1.1\times {10}^{-3}{ms}^{-1}$ .

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Answer: (C) $1.0{m}^{2}{V}^{-1}{s}^{-1}$

Mobility

\mu =\dfrac{{V}_{d}}{E}

\Rightarrow \mu =\dfrac{{V}_{d}}{E}=\dfrac{{V}_{d}l}{V}=\dfrac{{V}_{d}l}{iR}=\dfrac{{V}_{d}Al}{i\rho l}

\mu =\dfrac{1.1\times {10}^{-3}\times \pi {\left(5\times {10}^{-3}\right)}^{2}}{5\times 1.7\times {10}^{-8}}

=1.0{m}^{2}{V}^{-1}{s}^{-1}

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Physics practice question on Current Electricity (Electric Current and Drift of Electrons), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

A current of 5A5A5A passes through a copper conductor (resistivity =1.7×10−8Ωm=1.7\times {10}^{-8}\Omega m=1.7×10−8Ωm ) of radius of cross-section 5mm5mm5mm . Find the mobility of the charges if their drift velocity is 1.1×10−3ms−11.1\times {10}^{-3}{ms}^{-1}1.1×10−3ms−1 .

JEE Main question paper PDF

More Physics practice

A current of $5A$ passes through a copper conductor (resistivity $=1.7\times {10}^{-8}\Omega m$ ) of radius of cross-section $5mm$ . Find the mobility of the charges if their drift velocity is $1.1\times {10}^{-3}{ms}^{-1}$ .