Correct Answer - Option 4 : meter
-1
Concept:
- The resistance (R) of a conducting wire depends upon the length of wire, cross-sectional of the wire, and its resistivity.
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Resistance is directly proportional to the length of the conductor and Inversely proportional to the cross-sectional area.
The resistance (R) of a conducting wire depends upon the length of wire, cross-sectional of the wire, and its resistivity.
Resistance is directly proportional to the length of the conductor and Inversely proportional to the cross-sectional area.
\(R = ρ \frac{l}{A}\)
- Where l is the length of the conductor, a is the cross-sectional area of the conductor, ρ is resistivity.
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Resistivity: The resistivity is the resistor depends upon the nature of the conductor and temperature.
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Resistivity is the same for given conducting material at a given temperature and does not depend upon the dimensions of wire.
Calculation:
Given
\(R = ρ \frac{l}{A}\)
\(\implies \frac{R}{ρ} = \frac{l}{A}\)
So, the ratio of resistance and resistivity is the ratio of length and cross-sectional area.
Length has the unit meter, and area has unit meter2.
The unit of resistance and resistivity will be
\(\rm \frac{meter}{meter^2} = meter^{-1}\)
So, the correct option is meter -1
