The resistivity of a wire is _ohm-m if 0.75 A current flows through it by applying a 1.5 V potential difference. Take length and cross-section as 5m and 2.5 x 10^-7 m2.
Correct answer: A. 1 x 10^-7
- A. 1 x 10^-7
- B. 2.63 x 10^-8
- C. 19 x 10^-8
- D. 7.85 x 10^-8
Explanation
The resistivity (ρ) of the wire can be calculated using the formula: ρ = (RA) / L where R is the resistance of the wire, A is its cross-sectional area, and L is its length. The resistance can be calculated using Ohm's Law: R = V / I where V is the potential difference and I is the current. Given that the potential difference is 1.5 V and the current is 0.75 A, we can calculate the resistance of the wire as: R = V / I = 1.5 / 0.75 = 2 ohms Using the given values for length and cross-sectional area, we can calculate the resistivity as: ρ = (RA) / L = (2 * 2.5 x 10-7) / 5 = 1 x 10-7 ohm-m.
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