An overhead electric power line carries a maximum current of 125 A. What is the magnitude of the maximum magnetic field at a point 4.50 m directly below the power line?

Question

Quizplus · Accepted Answer

The magnetic field due to a long straight wire is given by:$$B = \frac{\mu_0 I}{2\pi r}$$where:* B is the magnetic field in teslas (T)* μ0 is the permeability of free space (4π × 10^-7 T·m/A)* I is the current in amperes (A)* r is the distance from the wire in meters (m)In this problem, we have:* I = 125 A* r = 4.50 mPlugging these values into the equation, we get:$$B = \frac{(4\pi 	imes 10^{-7} 	ext{ T$\cdot$m/A})(125 	ext{ A})}{2\pi (4.50 	ext{ m})}$$$$B = 5.56 	imes 10^{-6} 	ext{ T}$$Therefore, the magnitude of the maximum magnetic field at a point 4.50 m directly below the power line is 5.56 × 10^-6 T.

An Overhead Electric Power Line Carries a Maximum Current of 125