Physics 102
Practice Exam Problem #9


Electric power companies choose to transmit electrical energy over long distances at very high voltages and relatively low current. The same energy is used in households in the form of much lower voltage and higher current.
(a) Why are these sensible choices?
(b) Name the device that is used to change from high voltage and low current to the reverse.
(c) What law of physics does this device exploit?
("Short Answer" question from an actual former Physics 102 exam)
Solution

Physics 102 HW page