Question

The resistance of a wire of length 300m & cross-section 1 mm² & resistivity 1 x 10-7ohm is​

Answer 1

d) 30 Ω

Resistance, R = frac{rho l}{A}

Length, l = 300 m

Cross-section area, A = 1.0 mm2 = 10-6 m2

Resistivity, rho = 1.0 × 10−7 Ωm

Resistance, R = frac{10^{-7} times 300}{10^{-6}}

R = 30 Ω

Answer 2

Answer:

The answer to this question is = 30 ohm.

Explanation:

Given:

Length = 300 m

A = 1 mm² = 1 * 10^-6 m²

resistivity = p = 1 * 10^-7 ohm m

Resistance = R

R = p*l/A

R = 1 * 10^-7 * 300 / 1 * 10^-6

R = 300 * 10^-1

R = 30 ohm.

I HOPE IT WILL HELP YOU.