A long, straight wire with 3.0 A current flowing through it produces magnetic field strength 1.0 T at its surface. If the wire has a radius R, where within the wire is the field strength equal to 36% of the field strength at the surface of the wire? Assume that the current density is uniform throughout the wire. (μ₀ = 4π × 10^-7 T ∙ m/A) A) 0.36 R B) 0.060 R C) 0.64 R D) 0.030 R

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Quizplus · Accepted Answer

The magnetic field inside a wire with uniform current density is proportional to the distance from the center. To find where the field is 36% of the surface field, set B = 0.36 * B_surface and solve for the distance from the center, which is 0.36 R.

A Long, Straight Wire with 3