You and your team are exploring an abandoned science facility on the coast of western Antarctica when a large storm hits, and it is clear that you will be stuck there for a few days. You and the others search for supplies and fi nd a generator and a tank of fuel. Having electrical power would allow you to keep your communication devices operational and make your stay more comfortable. A team member gets the generator running, but there is a complication: The output of the generator is 50 Hz at 440 VAC (RMS), and your devices require 60 Hz, 110 VAC (RMS). The electrical power in many European countries runs on 240 V at 50 Hz, so a few of your team members have converters. However, 440 V is still too high to use them. You search and eventually fi nd a large transformer that, according to a worn tag on its case, is designed to step down from 5000 V to 880 V.

The tag also indicates that its primary coil has 1500 turns, but you cannot read the number of turns in the secondary coil.

(a) How many turns should its secondary coil have?

(b) It will be a difficult job, but you can change the number of primary turns by cutting some of them out. How many turns should you leave on the primary coil so that, with the primary connected to 440 V, the secondary outputs 240 V (so that you can use the 240 V to 110 V converters)?

(c) You fi nd that the current at the source (i.e., that connected to the primary) is limited to a maximum of 20.0 A. What is the maximum current limit through the secondary coil?

(d) What is the maximum average power available at the secondary coil?