CalculationsCâu 21 / 110
A 120-V branch circuit carries 16 A over a one-way run of 80 ft using #12 Cu (circular mils = 6,530, K = 12.9). What is the approximate voltage drop?
a.5.1 V
b.3.0 V
c.2.5 V
d.7.4 V
Giải thích
Single-phase VD = (2 x K x I x L) / CM = (2 x 12.9 x 16 x 80) / 6,530 = 33,024 / 6,530 = 5.06 V.
Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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