accelerometers - 2025 ACF Nationals

Tossup

After a “Mueller mechanical integrating” type of these devices was discovered in an unexploded V-2 rocket, Charles Stark Draper adapted it into a type still used in modern missiles. (-5[1])Thermal examples of these devices lack moving parts and work by measuring the asymmetry of temperature distribution (-5[1])around a bubble in a sealed space. The GOCE (“GO-chey”) spacecraft contains three pairs of highly accurate (-5[1])examples of these devices to try to find the exact (-5[1])shape of the geoid. (-5[2])MEMS examples of these devices (10[1])consist of a seismic mass and a cantilever beam. (10[1]-5[1])Spring-based examples (10[1])of these devices give a value of (-5[1])[read slowly] “the spring constant times distance moved by a mass, all (-5[1])over the test mass.” In smartphones, (10[1]-5[1])these devices can trigger (10[1])screen (10[1])rotation (10[2]-5[3])by determining orientation (10[1]-5[2])changes. For 10 points, name these devices that measure the rate of change of velocity. (10[14]0[1])■END■

ANSWER: accelerometers [accept Mueller mechanical integrating accelerometers or pendulous integrating gyroscopic accelerometers or MEMS accelerometers or PIGA accelerometers or gravimeters; prompt on gradiometers; prompt on gyroscopes until “bubble” is read by asking “what other device is the gyroscope a part of?”; reject “gyroscopes” after “bubble” is read]

= Average correct buzz position

Answerline and category may not exactly match the version played at all sites

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Buzzes

Player	Team	Opponent	Position	Value
Aidan Roullet	RIT	Illinois B	28	-5
Qingyu Zhang	Florida	NYU	45	-5
Karan Gurazada	Texas	Cornell A	61	-5
Jim Fan	North Carolina A	Columbia A	71	-5
Alex Akridge	Indiana	Illinois A	75	-5
Joy An	Harvard	Toronto B	75	-5
Jonathan Huang	MIT	Toronto C	80	10
Colin Veevers	Ottawa	Waterloo B	89	10
June Yin	WUSTL B	Penn State	89	-5
Swapnil Garg	UC Berkeley A	Waterloo A	91	10
Joseph Chambers	Virginia	Michigan	98	-5
Roxanne Tang	Ohio State	North Carolina B	108	-5
Sky Li	Toronto A	Stanford	114	-5
Matt Schiavone	Northwestern	WUSTL A	114	10
Vinu Harihar	UC Berkeley B	Arizona State	118	10
Andrew Wang	Illinois A	Indiana	119	10
John Marvin	Chicago A	Rutgers	120	10
Conor Thompson	Iowa State	Virginia Tech	120	10
Olin Bose	Columbia B	Maryland	120	-5
Thomas Tibbetts	UCF	Cornell B	120	-5
Gavin Markoff	Vanderbilt	Winona State	120	-5
Matthew Wang	British Columbia	LSE	123	-5
Andres Cordoba	Yale	Georgia State	123	-5
Rohan Dalal	Georgia Tech	Johns Hopkins	123	10
Albert Yingzhi Nyang	LSE	British Columbia	139	10
Shardul Rao	Minnesota	Chicago B	139	0
Liam Starnes	Chicago B	Minnesota	139	10
Richard Niu	Cornell A	Texas	139	10
Ryan Rosenberg	NYU	Florida	139	10
Amogh Kulkarni	Georgia State	Yale	139	10
Shardul Parthasarathy	Illinois B	RIT	139	10
Isaac Mammel	Maryland	Columbia B	139	10
Todd Maslyk	Michigan	Virginia	139	10
Geoffrey Wu	Columbia A	North Carolina A	139	10
Soren Heydari	North Carolina B	Ohio State	139	10
Michał Gerasimiuk	Stanford	Toronto A	139	10
Kunaal Chandrashekar	Toronto B	Harvard	139	10
Yared Tadesse	Cornell B	UCF	139	10
Ani Perumalla	Penn State	WUSTL B	139	10

Summary

Tournament	Exact Match?	TUH	Conv. %	Power %	Neg %	Average Buzz
2025 ACF Nationals	Yes	24	96%	0%	63%	126.96