Sub-topic 1
2026 · National Quarterfinal
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Emf induced by mutual inductance from a changing current
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Sub-topic 2
2018 · National One-Eighth
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Transformer secondary voltage from the turns ratio
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Sub-topic 3
2023 · National One-Eighth
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Problem of the day: transformer turns ratio, voltage and current
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Sub-topic 4
2021 · National Preliminary
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Emf induced in an inductor from a changing current
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Sub-topic 5
2021 · National Preliminary
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Emf induced in an inductor and finding inductance
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Sub-topic 6
2021 · National Preliminary
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Emf induced from a changing magnetic flux
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Sub-topic 7
2024 · National One-Eighth
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Problem of the day: solenoid magnetic field, flux, and induced emf from a rotating loop
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Sub-topic 8
2003 · National Semifinal
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Induced emf from a changing magnetic flux (faraday's law)
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Sub-topic 9
2012 · National Preliminary
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Riddle: lenz's law, the direction of induced emf
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Sub-topic 10
2013 · National Preliminary
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Transformer secondary voltage from the turns ratio
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Sub-topic 11
2013 · National Preliminary
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Transformer primary current from the turns ratio and secondary current
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Sub-topic 12
2013 · National Preliminary
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Transformer input power from the turns ratio, secondary current and input voltage
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Sub-topic 13
2014 · National Quarterfinal
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Problem of the day: resistivity unit conversion, wire length, and transformer primary current for a heating element
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