Field of a long wire: Two long parallel wires carry currents of 10 A in opposite directions. They are separated by 40 cm. What is the magnitude of the magnetic field in the plane of the wires at a point that is 20 cm from one wire and 60 cm from the other? (μ₀ = 4π × 10^-7 T ∙ m/A)

Question

Quizplus · Accepted Answer

The magnetic field due to a long straight wire is given by B = (μ₀I)/(2πr). Calculate the fields due to each wire at the point and subtract them because the currents are in opposite directions. The net field is 6.7 µT.

Field of a Long Wire: Two Long Parallel Wires Carry