Resistivity of a wire is_ohm-m if 0.75 A current flows through it by applying 1.5 V potential difference, take length and cross section as 5m and 2.5 x 10^-7 m^2.
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
Given: Current = I = 0.75 APotential difference = V = 1.5 V Length = L = 5 mCross-sectional area =A= 2.5 × 10-7m² Resistivity = p = ?Solution:As, V = IR R = V / I = 1.5 / 0.75 = 2 ΩAs we know that: R = pL / A p = RA / L = 2 × 2.5 × 10-7 / 5 = 5 × 10-7 / 5 p = 1 × 10-7 Ωm
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