A transformer connected to a 100 V (rms) ac line is to supply 8.0 V (rms) to a portable electronic device. The total equivalent resistance of the system is 5.00 ?.
(a) What should the ratio of primary to secondary turns of the transformer be?
(b) What rms current must the secondary supply?
(c) What average power is delivered to the load?
(d) What resistance connected directly across the 100 V line would draw the same power as the transformer?