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प्रश्न
A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 × 10−7 m2, and its resistance is measured to be 5.0 Ω. What is the resistivity of the material at the temperature of the experiment?
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उत्तर
Given: Length of the wire, l = 15 m
Area of cross-section of the wire, A = 6.0 × 10−7 m2
Resistance of the material of the wire, R = 5.0 Ω
To find: Resistivity of the material of the wire ρ = ?
Formula: Resistance is related to resistivity as,
R = `ρ l/A`
ρ = `(RA)/l`
= `(5.0 xx 6.0 xx 10^-7)/15`
= `(30 xx 10^-7)/15`
= 2 × 10−7 Ω m
Therefore, the resistivity of the material is 2 × 10−7 Ω m.
संबंधित प्रश्न
What conclusion can you draw from the following observations on a resistor made of alloy manganin?
| Current A |
Voltage V |
Current A |
Voltage V |
| 0.2 | 3.94 | 3.0 | 59.2 |
| 0.4 | 7.87 | 4.0 | 78.8 |
| 0.6 | 11.8 | 5.0 | 98.6 |
| 0.8 | 15.7 | 6.0 | 118.5 |
| 1.0 | 19.7 | 7.0 | 138.2 |
| 2.0 | 39.4 | 8.0 | 158.0 |
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