bullets - 2026 ACF Regionals

Question

The efficacy of these projectiles at harming is explained by the extremely controversial “hydrostatic shock” mechanism. For 10 points each:

[10e] Name these projectiles propelled using smokeless powder whose performance is often studied using ballistic gel.

ANSWER: bullets [or rounds; or ammo; or ammunition]

[10m] The effect that bullets have on their targets is studied in a subfield of ballistics described by this adjective. A quantity described by this adjective is derived by setting weight equal to one-half drag coefficient times area times velocity squared.

ANSWER: terminal [accept terminal ballistics; accept terminal velocity]

[10h] Very-low-drag bullets are often given a nose cone of this shape to minimize the effect of air resistance. A supersonic body with this profile has the minimum drag for any given value of volume and length.

ANSWER: Sears–Haack body [or Sears–Haack profile; prompt on SH body or SH profile]

<GC, Physics>

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Summary


California (South)	Main Site	Y	4	12.50	100%	25%	0%
Canada	Main Site	Y	10	11.00	100%	10%	0%
Lower Mid-Atlantic	Main Site	Y	1	10.00	100%	0%	0%
Lower Mid-Atlantic	Main Site	Y	6	10.00	100%	0%	0%
Midwest	Main Site	Y	8	11.25	100%	0%	13%
Northeast	Main Site	Y	5	8.00	80%	0%	0%
Overflow	Main Site	Y	3	13.33	100%	33%	0%
UK	Main Site	Y	12	12.50	100%	25%	0%

Data


UC Santa Barbara	Arizona State	10	0	0	10
UC Irvine	UCSD C	10	0	0	10
UCSD B	UCLA A	10	0	0	10
UCLA B	UCSD A	10	10	0	20
Toronto Metropolitan	Carleton University	10	0	0	10
McMaster A	Guelph	10	0	0	10
Queen's	Toronto B	10	0	0	10
Brock	Toronto D	10	0	0	10
Simon Fraser	Toronto E	10	0	0	10
Waterloo B	Toronto F	10	0	0	10
UBC A	McGill B	10	0	0	10
UBC B	Ottawa	10	10	0	20
McGill A	Waterloo A	10	0	0	10
Toronto G	Western B	10	0	0	10
Liberty B	NC State B	10	0	0	10
Liberty C	North Carolina A	10	0	0	10
Liberty A	North Carolina C	10	0	0	10
VCU	South Carolina A	10	0	0	10
South Carolina B	North Carolina B	10	0	0	10
Virginia Tech A	Virginia	10	0	0	10
William and Mary	Virginia Tech B	10	0	0	10
Indiana B	Chicago E	10	0	0	10
Chicago B	Chicago D	10	0	10	20
Chicago C	Chicago A	10	0	0	10
Notre Dame B	Northwestern D	10	0	0	10
Purdue A	Illinois B	10	0	0	10
Illinois C	Illinois A	10	0	0	10
Carleton College	Iowa State	10	0	0	10
Georgia Tech A	Missouri A	10	10	0	20
Claremont	Washington A	10	0	0	10
Harvard A	Bowdoin A	10	0	0	10
Bowdoin B	Southern Connecticut State	10	0	0	10
Brandeis A	Harvard B	0	0	0	0
MIT	Brandeis B	10	0	0	10
Brown	Yale	10	0	0	10
Southampton B	Oxford B	10	10	0	20
Oxford A	Warwick A	10	0	0	10
Warwick B	City St. George's	10	10	0	20
Birmingham	LSE	10	0	0	10
Imperial A	Cambridge A	10	0	0	10
Manchester	Cambridge B	10	0	0	10
Cambridge C	Oxford C	10	10	0	20
Imperial B	Durham	10	0	0	10
Edinburgh A	Bristol	10	0	0	10
Southampton A	Edinburgh B	10	0	0	10
Cardiff	Imperial C	10	0	0	10
UCL	Montpellier	10	0	0	10
Indiana A	Northwestern B	10	0	0	10
Northwestern C	Purdue B	10	0	0	10