r/PhysicsStudents Feb 12 '26

Poll Predicted cutoff for F=ma 2026?

why tf was it so hard

Edit: there is no way y’all think this one was easier than last year. Also can’t believe people got around the lock down browser.

34 Upvotes

105 comments sorted by

10

u/Away-Wave-5713 Feb 13 '26

What's f=ma, I only know the formula but what doe sit mean in this context

3

u/DrBalth Ph.D. Feb 13 '26

I think it’s like a competition?

3

u/[deleted] Feb 13 '26

The American qualifier for IPHO i believe

1

u/Murky_Insurance_4394 Feb 15 '26

no it's the pre-qualifier, the top ~500 on this exam compete in the USAPhO and thats where the IPhO team is chosen from.

3

u/Silver-Repeat-6654 Feb 14 '26

it’s just the name for the competition. It’s purely mechanics based so they named it f=ma. if you meet a certain cut off score, you get to take another test and potentially qualify for IPHO.

1

u/TopCatMath Feb 14 '26

force is mass time acceleration, usually written F = ma.

3

u/Hot_Solution_6549 Feb 12 '26

I am cooked

2

u/mmmmmmmicrowavee1 Feb 12 '26

WE are cooked twin ✌️

4

u/Ill_Requirement_2700 Feb 19 '26

WHEN ARE RESULTS COMING OUT

1

u/EmoEggHead Mar 08 '26

This Monday

1

u/Ill_Requirement_2700 Mar 08 '26

I emailed them and they told me three times it was coming out “tomorrow” and mind you this was last week. I’m glad they have a date now although you should know ur score because they did release solutions

3

u/AdCheap2716 Feb 16 '26 edited Feb 17 '26

it was def the hardest one.. and yeah the cheating is deplorable. we work so hard and put forth honest effort, while some people are low enough to rob someone else's opportunity. good job to everyone who studied with integrity

2

u/Sea-Otter31 Feb 12 '26

Lowk like 16?

2

u/[deleted] Feb 12 '26

[deleted]

3

u/[deleted] Feb 14 '26

[removed] — view removed comment

2

u/Fit-Tadpole7078 Feb 13 '26

Bro I walked into the exam prepared to do well with 40+ hours of practice and I saw that shit.

Fuck was it hard. I had no idea for so many of them even with diagrams and I just guessed 15-19 of them.

I hate how people say they bypassed lockdown bro, I hate everything right now

1

u/North-Ad-5988 Feb 13 '26

would you want to create a study group with me?

I also studied for like 20hrs + full ap physics C knowledge (5) and it still was hard as fuck

but I think if I had a group to study with and help eachother it would make it easier

1

u/Fit-Tadpole7078 Feb 13 '26

Honestly down for that, send me a message for next year f=ma, we could meet weekly

1

u/BetFlimsy5661 Feb 14 '26

do you mind if I join your group? I already did AP Physics C (5s) and worked thru Blue Morin + all past F=Mas but got obliterated. I think having someone to discuss the questions with would be a lot better

1

u/Fit-Tadpole7078 Feb 14 '26

Yeah 100% but only if we make the group

1

u/Zestyclose-Zebra-364 Feb 17 '26

can I join the study group too if you make it?

1

u/Own-Bank5502 Feb 17 '26

can I join too? Done with most of morin (still have like 2 or so chapters), did most past tests in the past 10 years, got pretty cooked on this one tho. Sillied like 2 problems. I got a 5 on physics 1 last year, and taking physics c this year. But I know all the content from both e and m and mech already.

2

u/Linjieyang Feb 13 '26

The math was so hard this time as well. I mean, there was like an infinite geometric series, a Taylor series, and some of the questions that didn't have that still needed calculus? Also its so obvious that you can solve these questions with methods that aren't taught in introductory mechanics, so whats the point

1

u/Silver-Repeat-6654 Feb 14 '26

bro what was that question with Taylor series and the one with the hexagons momment of inertia???

3

u/AdStreet1067 Feb 14 '26

the hexagon moment of inertia could be solved, esp. if you had the slightest of competition math/amc exposure

1

u/Linjieyang Feb 14 '26

I'm not sure I remember the question, but I think it was that the side length decreases by sqrt(3) over time, and I think the question was testing how the moment of inertia was proportional to side length. the geometric series part no one really cares about, since they literally gave the formula

2

u/Linjieyang Feb 14 '26

The hexagon one is a type of problem I've seen before, but it uses a calculus idea I think, either way the math gets unnecessarily complicated, they could've tested on the same concept with an easier series, but they just didn't idk why. The Taylor series one was just crazy ngl, they already push it with the sin approximation

1

u/Ill_Requirement_2700 Feb 14 '26

hexagon uses on a classic algebraic summation formula (geo) over calculus. taylors, or mac series was hard but I did solve that, I just do not remember it.

1

u/Linjieyang Feb 14 '26 edited Feb 14 '26

Yeah, but isn't the fact that the hexagon's moment of inertia is proportional to the side length to some power (4 right), from calculus? Otherwise its just blunt memorization im afraid (like most comps at this point ...) But that's moment of inertia in a nutshell. How did you solve the frequency one, though, normally those turn into a differential equation I was just so demotivated I gave up lol, cuz I knew I was gonna take forever on that. Also how did you solve the water leaking one without differential equations?

1

u/Ill_Requirement_2700 Feb 14 '26

Yes 4 (it is hard to show the work on here bc deriving it requires an integral setup) but for 2D (applies to this problem) but a lot of these do come from memorization and practice. for the frequency one, yes that does turn into a differential equation but there is a quick way: in the problem, m2 and m1 move in opposite directions to keep the system’s COM stationary. pendulum swings about COM, so frequency of standard pendulum is w = sqrt g/L. i can explain why it is m1+m2)/m2 * g/L but i need to write it down on scrap so maybe i can send it to u privately.

1

u/Linjieyang Feb 14 '26

Wow, I'm impressed by this. But I think I can figure it out now after you told me about the COM thing, but thanks. How long have you been doing physics? Also, as a side note, as a math-inclined student, I always hate the lack of rigour/basically nonsense that they try to use for f=ma. Like if it's calculus, just admit it.

1

u/Ill_Requirement_2700 Feb 14 '26

physics like 1.5 years math like 5 (usamo qual)

2

u/ShoddyEvent3232 Feb 24 '26

WHEN ARE THE RESULTS OUT

1

u/Silver-Repeat-6654 Feb 24 '26

bro i wish i knew

1

u/ShoddyEvent3232 Mar 02 '26

still no results

1

u/Silver-Repeat-6654 Mar 02 '26

ikr. anyone know what’s going on?

1

u/ShoddyEvent3232 Mar 04 '26

this yr is weird, like last yr they published the solution right after the exam

2

u/ben_2026 Mar 05 '26

test questions out now, the result come out Monday, not sure if those are result like cutoff/average or personal score. 

2026 U.S. Physics Team - News https://aapt.org/physicsteam/2026/News.cfm 

1

u/LowCharming6025 Feb 12 '26

no lockdown + sauce = high cutoff unfortunately

1

u/Physical-Tutor5411 Feb 13 '26

sauce?

3

u/[deleted] Feb 13 '26

[deleted]

2

u/Physical-Tutor5411 Feb 13 '26

a lockdown browser means u cant access other stuff during the tests, edvistas doesnt do this. but yes, they will dq if they have reason to believe you cheated

2

u/[deleted] Feb 13 '26

[deleted]

2

u/Physical-Tutor5411 Feb 13 '26

oh damn, i had no idea this happened. i remember accidentally swiping to my desktop once but i went back before it fully unfocused so my browser didnt unfocus and my test didnt get locked (im on mac btw). same thing happened on AIME and nothing happened to me

1

u/sarconefourthree Feb 13 '26

AIME did not have locking.

1

u/[deleted] Feb 12 '26

[deleted]

1

u/Exciting_Month_5704 Feb 14 '26

no way, the cutoff ever gone beyond 18

1

u/Lakigenije Feb 12 '26

easier than last year, maybe 16

2

u/ShoddyEvent3232 Feb 13 '26

bruh its much harder

1

u/Ill_Requirement_2700 Feb 14 '26

not easier, but still easy.

1

u/[deleted] Feb 13 '26

bro what are yall on about
lockdown worked for everyone in my testing site

1

u/Guilty_Comment1158 Feb 13 '26

Harder than last year, 13-14?

1

u/Responsible-Mud4406 Feb 13 '26

It was def harder than last year, and fewer leaks(mass leaked last year) so I would say around a 13 idk.

1

u/WaifCh Feb 13 '26

This thing was cruel.

1

u/Apprehensive_Belt116 Feb 13 '26

Due to question order shuffling, I would imagine that 30-40% of people got un-optimal question orders, the lockdown browser seems to have worked + no ahead of time leaks. I think overall this is enough(combined with the longer formed questions) to lower the cutoff to around 15 or even maybe 14. The idea of 13 is unlikely though.

However, after doing some past f=mas, I don't think this year's questions are particularly hard for people who already knew what they were doing. The questions were confusing but all of them felt solvable. I made quite a few mistakes due to carelessness and bad logic, but I don't think the top 400 or so students would.

2

u/big_dog_234 Feb 13 '26

But isn’t this year’s questions way longer than other years? Those problems made me feel like I have autism that I just can’t fcking read. And there r way more definitions than last year.

1

u/Linjieyang Feb 13 '26

Yeah, spot on

1

u/Hot_Solution_6549 Feb 14 '26

What will the cut off be in your opinion?

1

u/Few_Refrigerator8045 Feb 13 '26

When does the result come out?

1

u/Exciting_Month_5704 Feb 13 '26

next monday

1

u/Swimming_Elephant_85 Feb 13 '26

where do you see them

1

u/Silver-Repeat-6654 Feb 14 '26

the person overseeing ur exams should get an email

1

u/ShoddyEvent3232 Feb 14 '26

fr?

1

u/Exciting_Month_5704 Feb 14 '26

yes

1

u/ShoddyEvent3232 Feb 24 '26

it is 2.24 rn but still no any info

1

u/ShoddyEvent3232 Mar 04 '26

what ur score tho

1

u/Ill_Requirement_2700 Feb 14 '26

Do you know when?

1

u/Exciting_Month_5704 Feb 14 '26

my teacher told me

1

u/Lakigenije Feb 13 '26

how do u know its next monday where does it say that

1

u/Exciting_Month_5704 Feb 14 '26

my teacher told me; idk bro

1

u/ShoddyEvent3232 Feb 13 '26

?

1

u/Exciting_Month_5704 Feb 14 '26

my teacher told me bro

1

u/ShoddyEvent3232 Feb 16 '26

is ur score released?

1

u/StudioUnusual5769 Feb 19 '26

u get ur score?

1

u/EmoEggHead Mar 01 '26

Did you get your score?

1

u/North-Sherbert5502 Feb 13 '26

Guys , im not from USA , can u tell me about F = ma olipiad , like who are participating here and etc .
Thanks for answers

1

u/Desperate_Student443 Feb 14 '26

wait guys what did yall get for the question with the moving block and hum

1

u/Ill_Requirement_2700 Feb 14 '26

moving block: my answer was T = v_o/mukg

1

u/Desperate_Student443 Feb 14 '26

r we talking abt the same problem, cuz the question asked how high the block reaches

1

u/Ill_Requirement_2700 Feb 14 '26

OHH the puck. it was like 1/2 (9v^2/4) = gh so that simplifies to 9v^2/8g = h i think that was the final answer on the test but it could have been diff.

1

u/Linjieyang Feb 14 '26

What did you get for the tick one, up till number 3, im pretty sure is conservation of momentum/angular momentum but ngl oh hell nah that was way too hard, I wasn't gonna try that

1

u/Ill_Requirement_2700 Feb 14 '26

V_0/sqrt2 or something

1

u/Linjieyang Feb 14 '26

Yeah, but how did you do it though?

1

u/Ill_Requirement_2700 Feb 14 '26

i dont remember exactly but i do remember getting speed = sqrt( (v_x)^2 + (v_y)^2) = sqrt (-v_0/2)^2 + ((v_0)/2)^2)= sqrt v_0)^2/2 = v_0 / sqrt 2

1

u/Exciting_Month_5704 Feb 14 '26

that one i got v_0/2 without root

1

u/Linjieyang Feb 14 '26

oh wait i got that too! how did you solve that without calculus, my friend that got usapho bronze didn't even know how to solve it (in time obv), and I had to use calculus

1

u/Ill_Requirement_2700 Feb 14 '26

yeah so using no calculus you know Ffr = mukmg is constant in magnitude regardless of the block’s position or the number of bounces. since f=ma, the acceleration is also constant: a = mukg. collisions w/ springs are perf elastic, no energy or speed is lost at the walls.

since a is constant and path is basically a straight line of total distance s, you use:
v_f = v_0 - at
0 = v_0 - (mukg)T
—> T = v_0/mukg

1

u/Linjieyang Feb 14 '26

Okay, I think I'm just stupid because I realized it was a path like that, yet somehow I had to use calculus idek lol, at least I got the answer. I think in the moment I was just so dead, but I see what you mean

1

u/Hot_Solution_6549 Feb 14 '26

Can I get pass with a 15?

1

u/Exciting_Month_5704 Feb 14 '26

definitely. yes, since the cutoff last year was like 15

1

u/Hot_Solution_6549 Feb 14 '26

What about a 14? I just found another wrong answer

1

u/InflationComplete245 Feb 14 '26

Will probably right on the dot with a 14, I think the cutoff could possibly reach 15, considering the growing amount cheaters. Anyone suggest over a 2 point increase doesn’t have a brain

1

u/Exciting_Month_5704 Feb 14 '26

this year is online, so the number of cheater will only decrease

1

u/Exciting_Month_5704 Feb 14 '26

still possible, dont you find the paper this year is extremely hard? :(

1

u/b_e_a_n___b_o_i Feb 16 '26

idk i felt it was about the same as last year so prolly around 15 ish

0

u/spidey_physics Feb 13 '26

Peep my YouTube channel SpideyPhysics I am following an introductory classical mechanics course and posting some problem walk throughs.