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Modern transmission cables are ACSR or "Aluminum conductor steel reinforced" and are well suited to the above description of capacitance between parallel cables. One particular size of cable that we might experience is "single aught" (aught in this case is a size rating, you will often see it written as "0" while something like "double aught" is written as "00"). This size of cable can carry roughly 250 A current, has a diameter of 1 cm, and is perfectly suited to home power delivery. a. Compute the capacitance of such a pair of cables, if they are separated by 2m of air. This is how power is typically transmitted. Compute the capacitance of such a pair of cables, if they are separated by 1m of moist soll, where ε =20 Ep. It would be difficult to dig two trenches 2m apart for burying a single powerline. Digging one deep trench, however, is much more doable. Lets assume we lay 1 wire at the bottom of the trench, and the second wire about 1m above it in the same trench (with dirt in between of course). c. Compute the reactance of the two above capacitances assuming that this power is for residential use (f=60Hz). d. Describe the effect of having a capacitor shorting your AC load (as shown in the diagram below) at a very low frequency.

e. Describe the effect of having a capacitor shorting your AC load (as shown in the diagram below) at a very high frequency. f. Considering what we've seen in this assignment so far, why is it a good/bad idea to run our power cables underground? g. Considering the fact that these cables would have to exist in the real world, what are some other reasons for or against placing cables underground?

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