diffraction - 2025 ACF Fall

Tossup

This process is caused by devices partially named “echelle,” which have relatively few lines per millimeter. (10[1])Either prisms or devices named (10[1])for this process (10[1])are used as (10[1])dispersive (10[2])elements (10[3])in (10[1])spectrometers. (10[5]-5[1])The first zero (10[2])of the Bessel (10[1])function (10[1])J-sub-one (10[1]-5[1])equals the constant (-5[1])1.22 in Rayleigh’s (-5[1])criterion (10[1])for (10[1]-5[1])resolution (10[2])limited (10[1])by this (10[1])process. (10[6]-5[1])This (10[1])process’ (10[2]-5[1])intensity maxima occur (10[2])when sine theta (-5[1])is proportional (10[3]-5[1])to an integer multiple (10[2])of wavelength (10[1]-5[1])by Bragg’s (10[1])Law. (10[7]-5[2])Tightly (10[1]-5[1])spaced slits (10[2])make (10[1])up (10[1])gratings (10[2])named for (10[2])this (-5[1])process, (10[6]-5[1])which (10[1])light (10[1])undergoes (10[1]-5[1])before (10[2]-5[1])self-interfering (10[6]-5[1])in the double slit (10[1])experiment. (10[1])For 10 points, (-5[1])name this process in which light bends (10[2]-5[2])around (-5[1])an object. (10[1]-5[2])■END■ (10[14]0[22])

ANSWER: diffraction [accept diffraction gratings; prompt on dispersion before “dispersive” by asking “what causes the dispersion?”]

<Editors, Physics>

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Buzzes

Player	Team	Opponent	Position	Value
Martin Brandenburg	Georgia A	Tennessee Tech	15	10
David Yuan	Berkeley Little Prince	Stanford A	20	10
Saswat Sasha Tripathi	Chicago A	Iowa A	23	10
Dawson Teu	Waterloo A	Toronto D	26	10
Ethen Sun	Toronto C	Toronto A	27	10
Oliver West	Cambridge B	Cardiff	27	10
Advai Srinivasan	UC Irvine	UCLA F	28	10
Anne Fjeld	Alberta A	Washington Steelhead	28	10
Michael Shipman	Cambridge D	Bristol	28	10
Surya Dinesh	MIT A	Boston College A	29	10
Danny Han	Stanford B	Berkeley Archer Queen	30	10
Hansen Jin	Berkeley Skeleton King	UCSC	30	10
Jesse Mindel	NCSU A	UNC A	30	10
David Black	Illinois Champaign	Illinois Blue	30	-5
Tal Bowen	Durham A	Edinburgh A	30	10
Rory Moloney	Cambridge E	Imperial D	30	10
Wesley Stine	Clemson A	Georgia Tech C	33	10
Minh Nguyen	Cornell B	Binghamton C	33	10
Kevin Hendargo	UCSD A	UC Santa Barbara	36	10
David Latimer	Imperial A	Warwick	37	10
Cara Leonard	William & Mary C	William & Mary B	38	-5
Eleanor Arron	Williams C	Harvard	38	10
Nayaaz Hashim	Oxford	Cambridge A	41	-5
Liam Rojas	Virginia A	William & Mary A	44	-5
Shaya Farahmand	Georgia Tech B	Georgia Tech F	45	10
Alden Thompson	Carleton A	Carleton B	46	10
Henry Nonnemaker	CWRU C	Ohio State C	46	-5
Denali Tran-Le	McGill B	McGill A	47	10
Jeremy Scurlock	Chipola College	Alabama A	47	10
Jason Thieu	Michigan State A	Michigan B	48	10
Pace Klein	CWRU B	Louisville A	50	10
Annika Larson	Claremont A	Claremont B	51	10
Andrew Nucci	UCLA B	UCLA D	51	10
Brendan Bridle	Queen's A	Toronto F	51	10
Matthew Westley	Purdue A	Purdue C	51	10
Zach Majorowicz	St. Thomas	Wisconsin A	51	10
Daniel Lu	Washington Pink	Washington Sockeye	51	10
Towery McNeil	Mississippi State A	Auburn C	51	-5
Beckett Pursey	Purdue B	Iowa B	52	10
Ryan Gomes	Florida Tech A	UCF A	53	10
Nathan Woolery	Louisville C	Ohio State D	53	-5
George Matsumura	Washington Chum	British Columbia C	53	10
Nick Machin	UCLA A	USC A	56	10
Carter Yott	McMaster A	Toronto B	56	10
Jason Lee	Rutgers A	Maryland C	59	-5
Joseph Wang	UCLA E	USC B	61	10
Platon Gorokhov	Toronto E	McMaster B	61	-5
Nina Chen	Waterloo B	Waterloo C	61	10
Austin Tran	Rose-Hulman A	William Woods University A	61	10
Ty Brennan	Berkeley Mighty Miner	Berkeley Boss Bandit	65	10
Dustin Sanders	Chicago B	Illinois Urbana	65	10
Ethan Ririe	UCSD B	UCLA C	67	10
Francis Dinh	Illinois Canada	Indiana A	67	-5
Sicheng Jiang	Toronto H	Brock A	69	10
Sai Subramanian	CWRU A	Michigan A	70	10
Joseph Strom	Louisville B	Michigan C	70	10
Zachary Bornstein	Virginia Tech A	Virginia Tech B	70	10
Ben Weng	Macalester	Iowa State	70	10
Samarth Prajapati	Georgia Tech E	Emory A	70	10
Caleb Slusher	South Carolina A	Vanderbilt A	70	10
Nathan Whittington	Tennessee A	Georgia Tech A	70	-5
Brayden Zhang	Vanderbilt B	Vanderbilt C	70	-5
Vishrut Pisupati	Imperial B	Cambridge C	70	10
Malcolm Meyn	McGill C	Ottawa B	71	-5
Joshua Lam	Ohio State B	CWRU D	71	10
Matthew Lam	Ohio State A	Michigan State B	73	10
Anirudh Terdal	LSE	Imperial C	73	10
TJ Pickering	Auburn B	Auburn A	74	10
Charlotte Nicholas	Durham B	Sheffield A	75	10
Camden Walker	WashU Grolars	Purdue D	76	10
Derek Li	Cornell A	ESF	76	10
James Haddix	Washington State	Arizona State A	78	10
Alex Forman	Cornell D	RIT B	78	10
John Shelley	Clemson B	Clemson C	79	-5
Monica Wang	Guelph A	Toronto G	80	-5
Luke Sauer	Michigan Tech	Wisconsin B	80	10
Mahathi Veluri	UConn A	Tufts B	80	10
Bharath Ram	Georgia Tech A	Tennessee A	80	10
James Bramley	Durham C	Edinburgh C	80	10
Mata Cooper	Southampton	Birmingham	80	10
Will Hoover	RIT A	Cornell C	80	10
Benjamin Turner	York	Edinburgh D	81	10
Thomas Brittain	McMaster C	Toronto I	82	10
David Ropp	Duke A	Liberty A	83	-5
Alan Cai	Amherst A	Brown A	83	10
John Rootham	Ottawa D	Ottawa A	84	-5
Xavier Bornhorst	Maryland A	George Mason A	84	10
Ariyan Miah	Binghamton B	Rochester	84	10
Juan Landaeta	Florida State A	South Florida A	85	10
Nishad Joshi	Kentucky	Louisville D	85	10
Kevin Nolan	NCSU B	Liberty C	85	-5
Vivian Lu	Wisconsin C	Minnesota	85	10
Kyle Hart	MIT B	Brandeis Beethoven	85	10
Logan Van Pelt	Washington Coho	Arizona State B	85	10
Sonali Srikanth	Georgia Tech D	Montevallo	85	10
Sam Hewitt	WashU Grizzlers	Indiana B	89	10
Sam Kung	UNC C	Virginia Tech C	90	10
Bokei Thompson	Amherst B	Tufts C	93	-5
Jacob Ergueta	Florida A	Florida B	100	10
Atreya Mallanna	Brown B	Dartmouth B	100	-5
David Ciardella	Vermont B	Dartmouth A	100	-5
Grace Lovitt	Washington Masu	Boise State	100	10
Levan Tsiskarisvili	JMU B	Liberty B	101	-5
Pratham Bhanushali	WVU B	Michigan State D	103	10
Salil Jain	Williams B	Brandeis Mozart	103	-5
Rob Morris	Durham D	Edinburgh B	103	-5
Anjali Rao	Ottawa B	McGill C	104	0
Charlie Rickards	Ottawa C	McGill E	104	0
Neela Perceval-Maxwell	McGill E	Ottawa C	104	10
Aedan Cooper	Ottawa A	Ottawa D	104	0
Liam Henderson	McMaster B	Toronto E	104	10
Andrew Lin	Toronto G	Guelph A	104	10
Orin Overmiller	Florida Tech B	ERAU Daytona A	104	0
Heidi Moyer	ERAU Daytona A	Florida Tech B	104	0
Miles Spieler	Ohio State C	CWRU C	104	10
Akhil Upadrasta	Ohio State D	Louisville C	104	10
Varun Ramanathan	Michigan D	Pittsburgh	104	0
Zac Stapler	Pittsburgh	Michigan D	104	0
Chase Moss	WVU A	Michigan State C	104	0
Eric Cameron	Michigan State C	WVU A	104	0
Nathan Redford	Liberty A	Duke A	104	10
Jaden Rupolo	Liberty B	JMU B	104	0
Gabriel Dodds	Liberty C	NCSU B	104	0
Nghia Khau	VCU A	UNC B	104	10
Derek Aldridge	William & Mary A	Virginia A	104	0
William Erwin	William & Mary B	William & Mary C	104	0
Ben Spirtas	Maryland C	Rutgers A	104	0
Jiping Fang	Illinois Blue	Illinois Champaign	104	10
Trenton Burgess	Indiana A	Illinois Canada	104	10
Thomas Newill	Tufts C	Amherst B	104	0
Kenner Bailey	Boston University A	Brandeis Bach	104	0
Nathaniel Martin	Brandeis Bach	Boston University A	104	10
Alice Zhang	Dartmouth A	Vermont B	104	10
Jonathan Schnipper	Brandeis Mozart	Williams B	104	10
Joyann Hua	British Columbia B	Washington Atlantic	104	10
Justin Gilbert	Auburn C	Mississippi State A	104	0
Jacie Bradley	Clemson C	Clemson B	104	0
Nelson Adams-Riley	Sewanne	Tennessee B	104	0
Richard D’Angelo	Tennessee B	Sewanne	104	0
Edward Zhang	Vanderbilt C	Vanderbilt B	104	0
Leona Barker	Edinburgh B	Durham D	104	0
Antara Bhattacharya	Cambridge A	Oxford	104	10

Summary

Tournament	Edition	TUH	Conv. %	Neg %	Average Buzz
UK (North)	UK	5	80%	20%	66.50
UK (South)	UK	8	100%	13%	56.13
Northern California	US	4	100%	0%	36.25
Southern California	US	7	100%	0%	50.00
Eastern Canada (1)	US	5	60%	40%	65.67
Eastern Canada (2)	US	9	100%	22%	64.44
Florida	US	4	75%	0%	79.33
Great Lakes	US	12	83%	17%	77.80
Lower Mid-Atlantic	US	9	56%	56%	79.60
Upper Mid-Atlantic	US	2	50%	50%	84.00
Midwest	US	9	100%	22%	69.44
North	US	4	100%	0%	71.50
Northeast	US	10	80%	40%	78.38
Pacific	US	7	100%	0%	71.29
Southeast	US	13	69%	31%	57.67
Upstate NY	US	5	100%	0%	70.20