Kiểm tra & Khắc phục sự cốCâu 489 / 521
A DMM reads 12 V across a resistor and a clamp meter reads 3 A through it. What is the resistor's value?
a.36 ohms
b.4 ohms
c.0.25 ohms
d.15 ohms
Giải thích
R = V / I = 12 V / 3 A = 4 ohms. Option a multiplies V x I (that yields watts, 36 W), c inverts to I / V, and d adds the values.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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