Theory & Safety第 107 / 120 题
What power is consumed by a 120-volt load drawing 12 amperes at unity power factor?
a.1,440 watts
b.10 watts
c.132 watts
d.1,200 watts
解析
Power in a resistive single-phase circuit is P = E x I = 120 x 12 = 1,440 watts. The 10-watt answer divides instead of multiplying, 132 watts adds the two values, and 1,200 watts does not follow from the given numbers.
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