Question

Observation of the formation of these phenomena is the general goal of nondestructive testing of ferrous compounds using MPI. In quasi-static conditions, the power dissipation due to these phenomena is inversely proportional to a constant that is 1 for a sheet and 2 for a wire. Waste sorting at recycling facilities use these phenomena to separate metallic materials. (-5[1])In transformers, power loss caused by these phenomena can be minimized using laminated conductors and ferrite cores. Generation of these phenomena is used in braking systems often employed by roller coasters. These phenomena form due to a magnetic response as a consequence of Lenz’s law. For 10 points, what phenomena (10[1])consist of electric charges moving in closed loops during induction, (-5[1])named for their resemblance to whirlpools? ■END■ (10[1]0[1])

ANSWER: eddy currents [or eddies or Foucault’s current; prompt on currents; prompt on electromagnetic induction until read; prompt on magnetism or magnetic fields until “magnetic” is read]
<UW B, Physics>
= Average correct buzz position

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Buzzes

PlayerTeamOpponentBuzz PositionValue
Ian SaylorWisconsin BWinona State57-5
JD KrothIowa StateWisconsin A10710
Yash TiwariMinnesota BCarleton117-5
Aaron MarchandCarletonMinnesota B1240
Henry BonWinona StateWisconsin B12410

Summary

California2025-02-01Y3100%0%67%107.67
Florida2025-02-01Y250%0%100%124.00
Lower Mid-Atlantic2025-02-01Y667%0%17%83.50
Midwest2025-02-01Y6100%0%17%87.83
North2025-02-01Y367%0%67%115.50
Northeast2025-02-01Y580%0%60%106.25
Overflow2025-02-01Y580%0%20%85.25
South Central2025-02-01Y2100%0%50%111.50
Southeast2025-02-01Y4100%0%0%75.75
UK2025-02-01Y1090%0%10%78.11
Upper Mid-Atlantic2025-02-01Y8100%0%13%88.13
Upstate NY2025-02-01Y3100%0%33%97.00