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Two Resistors a and B Have Resistances Ra and Rb, Respectively, and Ra < Rb. the Resistivities of Their Materials Are ρA and ρB.

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प्रश्न

Two resistors A and B have resistances RA and RB, respectively, and RA < RB. The resistivities of their materials are ρA and ρB.

पर्याय

  • ρA > ρB

  • ρA = ρB

  • ρA < ρB

  • The information is not sufficient to find the relation between ρA and ρB

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उत्तर

The information is not sufficient to find the relation between ρA and ρB

 

The resistance R of a conductor depends on its resistivity ρ, length l and cross-sectional area A. Thus,

\[R = \rho\frac{l}{A}\]

From the given comparison of resistances, we cannot derive the correct relation between the resistances. We also need to know the cross-sectional areas and the lengths of both the conductors before concluding about their resistivities. Only then can the relation between the resistivities be found.

The information is not sufficient to find the relation between ρA and ρB.

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 32: Electric Current in Conductors - MCQ [पृष्ठ १९६]

APPEARS IN

एचसी वर्मा Concepts of Physics Volume 1 and 2 [English]
पाठ 32 Electric Current in Conductors
MCQ | Q 2 | पृष्ठ १९६

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