JEE PHYSICS MCQ: CURRENT ELECTRICITY

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If the free electron density be n and relaxation time be

\tau

, the electrical conductivity of a conductor may be expressed as

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Correct option: B

\frac{{n{e^2}\tau }}{{{m_e}}}

Option B (

\frac{{n{e^2}\tau }}{{{m_e}}}

) is correct because the electrical conductivity is directly proportional to the free electron density, the square of the electron charge, and the relaxation time, and inversely proportional to the electron mass.

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