Question

A horizontal power line (long straight wire) caries a current that varies sinusoidally with time at a rate of 60 Hz: I(t) = I₀sin(2πft), where I₀ = 55 kA is the amplitude of the current and f = 60 Hz. The wire is 7.0 m above ground. Farmer Joe, having learned some physics, knows that the alternating current in the wire produces an alternating magnetic field around it, and that if he were to place a coil of wire near the power line he could use the induced voltage to power some of his equipment. (a) Assuming the loop is placed directly underneath the power line, how should the loop be oriented to maximize the induced emf? (b) Assume the loop is rectangular with a height of 2.0 m and a width of 12 m. How many turns of wire will the loop need to generate the 170 V peak emf Joe’s equipment requires? [An integral will be required.] (c) Is this ethical?

Answer 1

Solution :-