A power transmission line 50 km long has a total resistance of 0.60 W. A generator produces V at 70A. In order to reduce energy loss due to heating of the transmission line, the voltage is stepped up with a transformer with a turns ratio of 100:1. What percentage of the original energy is lost when the transformer is used?

Faraday's law: A changing magnetic field induces an emf.

Lenz's law:  current produced by an induced emf moves in a direction so that its magnetic field opposes the original change in flux.

The three ways that an emf can be induced in a loop of wire.
1. by changing the magnetic field
2. by changing the area of the loop in the field
3. by changing the loop's orientation with respect to the field