Kiểm tra & Khắc phục sự cốCâu 519 / 521
A motor-control resistor of 15 ohms must carry 2 A during operation. What voltage drop will a DMM read across it?
a.7.5 V
b.30 V
c.0.13 V
d.17 V
Giải thích
V = I x R = 2 A x 15 ohms = 30 V. Option a divides R by I, c inverts to I / R, and d adds the two numbers, none is Ohm's law.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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