Theory & SafetyCâu 106 / 120
A heating element of 30 ohms is connected across 240 volts. What current flows?
a.8 amperes
b.0.125 ampere
c.7,200 amperes
d.12 amperes
Giải thích
Ohm's law gives I = E / R = 240 / 30 = 8 amperes. The 0.125-ampere answer inverts the division, 7,200 multiplies voltage by resistance instead of dividing, and 12 amperes would require a 20-ohm element.
Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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