A high-voltage power line 20 m above the ground carries a current of 5000 A.What is the magnetic field due to the current directly underneath the power line? (µ₀ = 4π × 10−⁷ T⋅m/A) A) 14 mT B) 35 µT C) 20 µT D) 50 µT

Question

Quizplus · Accepted Answer

The magnetic field due to a long straight current-carrying wire is given by B = (µ₀I)/(2πr). Substituting µ₀ = 4π × 10⁻⁷ T⋅m/A, I = 5000 A, and r = 20 m, we get B = (4π × 10⁻⁷ T⋅m/A × 5000 A)/(2π × 20 m) = 50 µT.

A High-Voltage Power Line 20 M Above the Ground Carries