Kiểm tra & Khắc phục sự cốCâu 506 / 521
A 6 ohm and a 3 ohm resistor are connected in parallel. What total resistance should an ohmmeter read?
a.9 ohms
b.4.5 ohms
c.2 ohms
d.18 ohms
Giải thích
Parallel: R = (R1 x R2) / (R1 + R2) = (6 x 3) / (6 + 3) = 18 / 9 = 2 ohms. The total is always less than the smallest resistor. Option a is the series sum, b the simple average, and d the product only.
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