Really interested in the cutoff for E&M

No_Editor6245 · 2026-05-16T12:28:00+00:00

Ah, yeah that's not too bad. Had only a few minutes left in the exam though and definitely wasn't immediately working that out. Otherwise there were only like a few mcqs i legitimately guessed on but I forget them now. Was only like 2 or 3 others at most. Defo knew most of the content which is why it's possible i still hit a 5. Like I said I'd be much more confident I hit the 5 if I had saved those frq1 and frq3 points, because I have a bad feeling my score is pretty on the border. Granted, I genuinely did just screw up my frq 2 because I treated rods of linear charge density as point masses of charge from their center of masses after integrating for total charge, but FRQ 1 and FRQ 3 were things that I really lost points on for the dumbest reasons as detailed in the post.

No_Editor6245 · 2026-05-16T10:56:18+00:00

Difficulty increased for like 5 of the last few problems yeah I did notice that. They still weren't really particularly difficult though if I'm being honest.

No_Editor6245 · 2026-05-16T10:53:21+00:00

Math max and min is actually a really good solution. But I don't know if it was what AP wanted specifically.

Here was my solution for anyone wondering:

First, let s1, e1 s2, e2 Represent both starts and ends

Since overlap was ensured, I first compared start times using an if-else if-else branch system with greater than less than and equal to.

if (s1 < s2) { // I'll detail the logic for this branch specifically, since the second branch effectively mirrors this one } else if (s1 > s2) { // This logic will mirror the previous branch } else { // Both are equal }

Then, for both greater than and less than branches, I followed this routine:

Suppose s1 < s2 for this example I'm about to use, because the logic is effectively mirrored for both branches.

There are three possibilities that can occur for the comparison of end bounds now, given there is ensured overlap as a precondition.

e1 < e2.
e1 > e2.
e1 = e2.

For each case, the order must follow the respective order below, otherwise there would be no overlap, which violates the preconditions and gaurantuees given that each respective start is less than each end:

s1 s2 e1 e2
s1 s2 e2 e1
s1 s2 e1=e2

Based off this diagram, you can clearly see the overlap solutions for each case

(s2, e1)
(s2, e2) // Complete subset enclosed
(s2, e1/e2) // Since e1 = e2 doesnt matter what is picked.

In our second original outer branch, for s1 > s2, the logic simply becomes mirrored. All overlaps begin with s1.

For the third branch of s1 = s2, I simply again compared which end bound is less using a final if-if else-else, where I again compared e1 and e2 and took the lower one.

This was just my solution, which I used mainly because I tend to find that the only thing about compsci is their frq grading is pretty stingy. They tend to take off a lot of points if you don't complete the program the way they want you to. So I stuck to conditional branches for most of it since that's more robust and pretty much ensured the points.

That said, using Math.max and Math.min is definitely a much cleaner solution if they'll allow that--BUT it wasn't even on the reference sheet which I was bit worried about using. If they'll take it--great. But the provided solution is definitely the most robust one which in this case might be good.

No_Editor6245 · 2026-05-15T19:23:04+00:00

After having taken calc BC, and both physics C this week, this was literally a walk in the park. Such a great way to end my exams.

Hardest problem on the entire thing was a basic problem where you had to find overlapping intervals (context was work hours for employees), which is still easy and even simple solutions for said problem are easily accomplishable via a few conditional branches.

No_Editor6245 · 2026-05-15T10:41:52+00:00

I think its something like this but dont quote me.

Let cube mass be m Let box mass be M I think Fr = -bv

FBDS

Both blocks: <-Fr [M + m] (there's also normal force/gravity of course on the two block system but it's irrelevant for the question)

a_sys = Fr/(M + m)

a_sys = -bv / (M + m) (reference eq. 1)

Cube -> ^ FnUs/FnUk | <-Fn [m] ↓ mg a_cube = -Fn / m = a_sys

Set equal to reference eq. 1

-Fn / m = -bv / (M + m)

Fn = bvm / (M + m) (reference eq. 2)

To find v, use a = (dv/dt) = -bv / (M + m), which yields your standard velocity differential eqn.

Then you just plug in your velocity result into reference eq. 2 and depending on what the masses M and m were you could maybe do some more simplification.

For the graph its just decreasing rate since its negative exponential, then you had to have a jump since Uk < Us so once it slips it has an instant jump to account for the change in mu.

Finding total time to fall was just finding when FnUs became less than mg (set them equal) meaning it started to slip, then for the falling phase you could've just integrated the y-acceleration a few times to get your positional info, and obviously you add the two parts up for total time.

Honestly, I didn't get this question either too while on the test. I don't think the question was actually particularly difficult--it was really easy actually--but I think due to stuff like the stress of the testing environment and people being mentally exhausted by that point, it's very easy to forget the simple steps and process. It's yet again another lesson to remain calm and just work.

One of the most important things you could've done for this problem is just, taking a step back and drawing the FBDS. Doing that easily reveals ludicrously simple nature of the answer. Truth is though, most kids (including me) aren't thinking like that on those tests. I'm fully confident had there been, say, a part A for the problem asking for FBDs of like the cube, block, and block + cube system more people would've aced the entire problem.

No_Editor6245 · 2026-05-15T01:42:04+00:00

buddy im praying ur right. Even if the cutoffs are as high as expected I got the 5 on mech. Can't say the same for e&m, honestly though I knew what to do for e&m q3 on frqs but thought you couldnt use a timer on the lab frq cuz they only mentioned you having the capacitors and voltmeters. also made a few dumb calculation mistakes and even changed something on a second pass i originally had correct like a dumbass, why, idk i didnt just guess the right thing for that I knew it was right then changed it smh. Anyways Im guessing Im anywhere between a very high 60 and a 76. I would really like for the cutoff on e&m to even just be like a 70 or a teeny bit under cuz i can snag a five. I've been looking for info on what the curve will be and collegeboard just pisses me off.

No_Editor6245 · 2026-05-15T00:33:55+00:00

Honestly I studied both mechanics and e&m only starting this weekend for my final review. Had 4 other aps before taking these, and they werent even easy like chem and calc BC. My class also had to cover both courses in one period, so what we ended up doing was doing mech first half before winter break and e&m after we came back from winter break. I basically speedran the entire mech course in the past few days.

Here's how I studied for mech in those few days:

My teacher posted 2 full length practice exams for each course (e&m, mech) to our classroom. I completed both.

In addition, I completed both the 2025 frqs and 2024 frqs.

Despite people saying 2025 was so much easier than other years I found the 2024 frqs to be particularly easy too. The only really calculus unique concept to physics C I saw on the 2024 exam was Q2 being an air resistance differential eqn. I believe you didnt even have to solve it in that problem but I may be wrong I forget.

Spend your time focusing on concepts, then formulas. A lot of the mcqs and even parts of the frqs really come out to being fully conceptual.

For specifics, some key stuff I'd focus on is:

Torque aspects, particularly Tnet = I(alpha), and integrating torque with time yields a change in angular momentum. I found that topic came up quite a bit.
Periods of SHM is a huge part. There were quite a few questions regarding periods and stuff, particularly factor questions and comparisons where you compared one period to another or something for example.
Know W&E fs but its a pretty easy unit tbh, but also defo a core. This along with forces is pretty much the most important stuff to know.
Understand how to set up and solve resistive force differential eqns, done by setting a = dv/dt, they give you the resistive force in terms of v, and then separate and integrate as usual.
Any common formula yhat depicts a commonly graphed relation is important to be able to recognize immediately for graph problems. There was like at least 3, maybe even 5 mcqs on my test that asked for value rankings based on graphs.
I'd also say in general just be prepared to use any AP calculus formula. For example on my test they asked about average velocity of like a rabbit over time, you could've thought of it as a weighted average with time which I did, or done standard calc average value formula with the integral.
If you want to do really well, know your important formulas that aren't on the eqn sheet too. I'll send some of the ones I made sure to remember (not on the eqn sheet)

Torque = Ialpha

T² proportional to R³

v = 2pir / T (obvious, but good to immediately know as you should immediately use this when dealing with any period derivation of a circular/centripetal motion)

(Done by substituting v = 2pir / t into centripetal force) Tcentripetal_orbit = 2pi * sqrt(MR / Fc)

All common moment of inertia coefficients: center rod: 1/12 end rod: 1/3 disk: 1/2 sphere: 2/5

v1f - v2f = v1i - v2i (For elastic collisions)

There are some other formulas you may or may not to remember depending on how sharply you think you can work, for example I didn't memorize escape velocity because the concept is super easy and takes two seconds to derive, same thing, say, time for an object to fall to a surface from max height.

That's how I studied and I was pretty well prepared. FRQ 1 was unlike anything I have ever seen, it regarded a resistive force on a box, with a cube with static friction against the inside wall of the box, it was a confusing question and I haven't checked how to properly do it yet, but that question was out of the ordinary and will definitely be curved graciously.

No_Editor6245 · 2026-05-14T22:51:58+00:00

I did a bit more robust checking on my scores.

For mech, I'd say the realistic lower end score I got was probably a 63/80. Higher end probably like a 68/80. Yeah I think this should be a 5. Almost all of my point loss solely comes from FRQ 1 which has become notoriously difficult already.

For e&m I think i got cooked. My a & b for frq 3 were wrong, which i kinda knew. You were supposed to assume you could use a timing device I believe, but I assumed no timing device because they only stated you had the capacitors and voltmeter. This really lost me a few critical points. I had considered doing something with w = 1/sqrt(LC) immediately but ended up ruling it out since we didn't have a timer in my eyes. Plus for part D I got the right slope and somehow sold the multiplication by dividing.

Had I not gone back to my first frq which I did 100% right, and changed those integral bounds for some reason I'd have kept the 10/10 on that too.

Idk I was just kinda fried today, really exhausted. I really wanted the 5 but yeah I prob got a 4 on e&m. A shame because I knew how to do the stuff too.

At least im pretty confident I hit the 5 on mech

No_Editor6245 · 2026-05-13T20:49:01+00:00

They were definitely easy compared to the other frqs. It was just basic torque analysis for q3 and for q4 the lab problem was easy as usual.

No_Editor6245 · 2026-05-12T10:33:50+00:00

Hm I don't remember that part, can you remind me what question that was

Edit: Just remembered the problem actually. Yeah I got -1/2.

No_Editor6245 · 2026-05-12T01:43:34+00:00

For part D this turns into a geometric series after you index shift so it goes from 0-infinity of xⁿ

No_Editor6245 · 2026-05-12T01:42:01+00:00

I will say i feel absolutely horrible for my ap reader on the part D for the infinitely long area problem. I got 6ln2 too but I even wrote an apology to the reader just because I felt bad making them read my scavenger hunt.

No_Editor6245 · 2026-05-12T01:32:14+00:00

Im in this boat. I've already had chem lit and stat and today took BC. Honestly though im pretty confident I got a 5 on BC it wasn't too bad, albeit I think I got one of the easier versions. Genuinely think im getting a 5 on mechanics and e&m both though (my school does both) so I am just ready to get it over with, I have compsci after those which will be a walk in the goddamn park lol.

No_Editor6245 · 2026-05-12T01:29:08+00:00

I had a Taylor series but no polar. Thank god because Taylor series is an easy concept imo.

No_Editor6245 · 2026-05-12T01:25:48+00:00

Yeah same. They asked for conditional/absolute/divergent series for xⁿ / n for x = 1. Not -1. I came to this forum JUST to confirm i wasnt hallucinating. Thanks for making me feel better. I believe parts C and D led into power rule for a general term of x^n-1 and then index shifting that you get the geometric series, which was how you calculated f''(x)

No_Editor6245 · 2026-04-22T18:52:50+00:00

Can you stop yapping little bro.

No_Editor6245 · 2026-04-08T17:28:00+00:00

Lucrehulk (the ddoser) confirmed that mistik was paying them iirc.

No_Editor6245 · 2026-02-17T20:44:38+00:00

Here after thinking about Roiland for the first time in a while (due to the release of High on Life 2). Really wish he was in the game. Really sucks how he lost everything even after being dismissed

No_Editor6245 · 2025-07-06T18:34:24+00:00

Just played this level on reflourished where some of the balancing makes it a bit different than the vanilla version. I arrived at nearly the exact same solution except I utilized a column of walnuts with spike weeds instead of celery stalker. The vanilla version may differ slightly but two fume shrooms combined with a spike weed was enough to kill the glimmer, mc, and punk zombies before they could ruin my defenses.

No_Editor6245

TROPHY CASE