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A type of motor named for this quantity delivers power to windings in the stator (“STAY-ter”) instead of the rotor. For 10 points each:
[10h] Name this quantity that for a uniform magnetic field equals one over permeability times the cross-sectional area of a circuit. Air gaps in flyback transformers drive increases in this quantity, which allows their cores to store more energy.
ANSWER: magnetic reluctance [accept switched reluctance motors; prompt on magnetic resistance; prompt on F; reject “electrical resistance” or “resistance”; reject “electric reluctance”]
[10m] By analogizing reluctance to resistance, reluctance equals magnetomotive force over this quantity. This quantity is the line integral of the vector potential over a surface’s boundary.
ANSWER: magnetic flux [prompt on flux; prompt on phi-sub-b or phi]
[10e] By using a model named for gyrators and these components, reluctance equals the rate of change of flux times magnetic resistance. These components consist of two metallic plates separated by a di·electric.
ANSWER: capacitors [accept parallel-plate capacitors or gyrator-capacitor model]
<Physics>
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Conversion

TeamOpponentPart 1Part 2Part 3TotalParts
British ColumbiaChicago A0101020ME
Columbia AToronto B001010E
Columbia BNorth Carolina B001010E
Cornell ANorth Carolina A001010E
Cornell BIndiana001010E
Georgia TechArizona State001010E
HarvardLSE001010E
MITIowa State0101020ME
MichiganWinona State001010E
NYUChicago B001010E
NorthwesternVirginia Tech0101020ME
Penn StateRutgers0101020ME
StanfordUC Berkeley B001010E
UC Berkeley ATexas001010E
UCFJohns Hopkins001010E
VanderbiltOttawa001010E
VirginiaRIT001010E
WUSTL AYale1001020HE
WUSTL BMinnesota0101020ME
Waterloo AMaryland001010E
Waterloo BToronto A0101020ME

Summary

TournamentExact Match?HeardPPBEasy %Medium %Hard %
2025 ACF NationalsYes2113.33100%29%5%