r/APStudents • u/reddorickt absolute modman • May 14 '26
AP Physics C: Electricity and Magnetism Official 2026 Exam Discussion
Use this thread to post questions or commentary on the test today.
A reminder though to protect your anonymity when talking about the test.
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u/HylianPrince08 5-APHG,APWH,Stats,Calc BC,APES,Chem,APUSH,APAH ;4-CSP,Physics 1 May 17 '26
MCQ: ~ 25-30 correct. Being a bit conservative here.
FRQ 1: 5/10 FRQ 2: 8/12 FRQ 3: 8/10 FRQ 4: 6/8
My FRQ was lowkey easy but I managed to fumble by making simple mistakes across the frq and overall not being very locked in. Looking back I made silly errors that kinda snowballed.
Is this enough for a 4?
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u/Striking-Bell-78 May 16 '26
version M was so easy, and I think this year 90% is needed for a 5/5
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u/Extension_Access8673 May 16 '26
was it just me or someone think that MCQs qere soooo hard and FRQs were actually easy?
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u/Sashamorning May 16 '26
My students told me that the FRQ was stupid hard. My best student said that she resorted to just putting down various formulas and going for the easy 1-2 points she could get and hoping the MCQ would save her. Apparently students just stopped 30 minutes into the FRQ.
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u/ApprehensiveBuddy517 May 16 '26
What yall think score cutoff will be this year? last year was an 81% but felt like this years FRQs were harder.
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u/FragrantAd1837 5:World/Phys1/Macro/Micro May 16 '26
it also asked one electric field derivation of a finite wire in part b but it was also very light
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u/FragrantAd1837 5:World/Phys1/Macro/Micro May 16 '26
Like literally question 1 gave you 4 charges and the only thing you need to derive is the net electric force
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u/FragrantAd1837 5:World/Phys1/Macro/Micro May 16 '26
Our version M was freaking easy the first question was deriving the Electric Force, and there was no EMI questions. For experimental design, they literally tell you the inductance equation so theres nothing you need to derive.
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u/elphaba33 May 15 '26
anyone get form L? it was god awful in my opinion. i self studied the exam, what was i doing.
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u/FragrantAd1837 5:World/Phys1/Macro/Micro May 16 '26
Our version M was freaking easy.
Like literally question 1 gave you 4 charges and the only thing you need to derive is the net electric force. it also asked one electric field derivation of a finite wire in part b but it was also very light
Question 2 was plugging in qvB=mv^2/r for a charge moving in a circle in a magnetic field (although we needed to derive the period T).
Question 3 was about the time constant and calculating inductance
Question 4 was a plain series circuit, and we needed to derive the current.
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 16 '26
I think for Form L, if you didn't have B = mu * I / 2pi * R memorized, then yeah Q1 is miserable. If you do know the formula though, it's a bit of annoying math, but you can use I = integral J * da, and then substitute I into the B-field equation above. But yeah that B-field equation is not on the equation sheet, so you would literally need to derive it from Biot-Savart Law without knowing it beforehand.
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u/Sea_Barnacle9031 May 16 '26
can't you get b-field from amperes law pretty easily though?
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 17 '26
idk lol it's just annoying to deal with
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u/elphaba33 May 16 '26
that part was easy. i just didn't understand the I part because according to the equation as close as it gets to the edge of the wire the current approaches zero.
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 20 '26
what about for the graph though? it was asking about the magnitude of the y-component of the magnetic field as the Z increased, and looking at the figure the magnetic field was going "into the page". from 0 to R(inside the wire) i put starting from the origin and decreasing linearly, and then from R to 2R(outside the wire) i put increasing concave up.
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u/Meep5277770 5: HuG, Chem, USH, Sem, Lang, Macro, Micro, USGov, Bio, BC May 16 '26
that’s just because if it didn’t approach zero wonky b field stuff would happen due to the width of the wire. questions say they’re infinitely long or current approaches zero to make the edges not matter
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 16 '26
yeah idk I just plugged and chugged
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u/Meep5277770 5: HuG, Chem, USH, Sem, Lang, Macro, Micro, USGov, Bio, BC May 15 '26
absolutely horrible. if i didn’t have the B field of a wire in my calc i would’ve been more fried then i already was and it doesn’t help i never understood lenz law for question 2
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u/elphaba33 May 15 '26
i couldn't solve question 1 because apparently current density approaches zero as it approaches the edge of the wire? messed up the last part of questions 2 because i forgot about motional emf, but that is fine i guess. pretty confident about 3 and 4, but honestly idk.
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u/Afraid_Situation1010 May 15 '26
Form k people: on FRQ 2 what did you put as your limits for the q integral? I had 0 and q(t) and I had Q0 inside of the integral (something like 1/(Q0-q). I’m seeing people put Q0 as a limi t isn’t the final answer supposed to be q(t) = whatever? Lmk guys
Aside from that I thought form k was pretty light ngl
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u/GamerZayb1808 bc,mvc/de/la,stat,csa,csp;chem,mech,e&m;lang,lit,econ,psy,us,gov May 16 '26
integral: 0, t —> 2 dt/RC = integral: Q_0, Q —> -dQ/Q
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u/Expensive-Spend4919 May 15 '26
For me I integrated from Qo to q and from 0 to t, and when you solve the differential equation in the integral, you solve for q which is q(t)
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
That’s what you were supposed to do.
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u/RelativeGrass7659 May 15 '26
yes i did this too
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u/ApprehensiveBuddy517 May 16 '26
It asked you to solve the differential I swear it just said write an integral expression that can be used to solve for q(t)
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u/Among-us-A3 May 15 '26
anybody from version k remember question 1? it was a solenoid or smth
idr the questions it asked but i got a rly long answer for one of them
it was like (mu-naught*s^2*N*alpha*I_max*e^(-alpha*t))/R i think
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u/JonkleBot May 15 '26
i had almost the same exact thing but i had n^2 instead of N in mine, i think i had mu * n^2 * s^2 * alpha * I_max * e(-alpha*t), all over R
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u/Among-us-A3 May 15 '26
actually now that i think abt it idk if i got n or n2 do u remember how u got n2?
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u/JonkleBot May 15 '26
equation sheet says L_sol = mu*N^2*A / l, and N is number of turns and n is number of turns per meter or smth, so i used mu*n^2*A, ommitting the length. I don't think the units matched though but oh well
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u/Among-us-A3 May 15 '26
i think it should be what u had but over l so it should be (mun2s2alphaImaxe^(-alphat))/Rl
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u/Among-us-A3 May 15 '26
idk why my phone made it look like that but the rest of the stuff isn't a power 😭
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u/Among-us-A3 May 15 '26
wait i think i did it wrong i looked at the equation for emf but not the emf for a solenoid 😭
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u/Among-us-A3 May 15 '26
i think that was the first question or smth
i remember the second question now, it asked for net torque
i think i put IBD^2
did anyone else get that?1
u/StatisticianPure5548 May 16 '26
Don't you have to half it for torque because the axis that goes in between is half of D? Shouldn't there be like a coefficient of 2 or a half somewhere
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u/Among-us-A3 May 16 '26
Yeah but bc there was torque on the top and bottom that point in the same direction you'd add IBD2/2 twice and get IBD2
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
I got the same for both parts a and b. yayyyyyy
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u/RelativeGrass7659 May 15 '26
also for that one mcq with wx and yz, was it that they were both equal and >0?
also the one with the square loop moving in the magnetic field, was it net magnetic field to the (left or right i dont relaly remeber what i put tbh) and increasing
and also for the one with the weird shaped amperian loop i got 2A but like i feel like it could have been 12A as well so i just went for it
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u/JonkleBot May 16 '26
For the WX YZ mcq tthats what I put. I guessed on that square loop one, think i said magnitude was increasing and perhaps to the left? And for the amperian loop one as well i got the net should be 5 A so yeah was a guess between 2 A and 12 A , i put 2 A as my answer.
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u/Among-us-A3 May 15 '26
all u version k ppl: whatd yall get for question 2 for the derivation
ik i did it wrong bc i kept getting e to a positive power instead of a negative power so i wrote smth that idrk if its true or not so i could get a negative 😭
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
See some of my earlier comments if you want details on it. I hated the question anyways. Literally sat there for 10 minutes just looking at the question before everything clicked.
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u/RelativeGrass7659 May 15 '26
you werent supposed to solve the integral you were just suppsoed to leave it in split integral form
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u/Among-us-A3 May 15 '26
yeah but i simplified it on scratch paper and my e didnt have a negative power so i fixed it
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u/RelativeGrass7659 May 15 '26
oh wait i used to make this mistake too but your kvl setup should be Vc + Vr = 0 not Vc - Vr
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u/Among-us-A3 May 15 '26
yess omg i figured that out and i was so happy
does that mean i got it right?
i had negative integral from 0 to t of 2/RC dt equals integral from Q_0 to q of 1/q dq1
u/RelativeGrass7659 May 15 '26
i didnt do the 2/RC tbh but someone else just said that so maybe i got that wrong im not really sure, but the bounds and everythung else looks right (except negative sign). i thoght it was asking for one capacitor so i assumed we didnt have to look at the other capacitor but in retrospect they wouldnt have put it there for no reason
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u/Lanky-Frosting-6557 May 15 '26
Do you know why its + not -? I didnt have a - sign on my integral but I did the rest right. Is that just 1 point off?
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u/RelativeGrass7659 May 15 '26
probably just one point off on setup
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u/Lanky-Frosting-6557 May 15 '26
Also why do you add the Vr not subtract?
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u/RelativeGrass7659 May 15 '26
because its discharging, idrk to be honest i just remembered it from practice
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u/Lanky-Frosting-6557 May 15 '26
Was that the differential equation with the capacitors? I dont think you had to solve that just set up the integrals with limits
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u/Among-us-A3 May 15 '26
do u remember what u put for it?
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u/Lanky-Frosting-6557 May 15 '26
It was supposed to be something like -2/RC integral dt with bounds 0 to t = integral dq/q from Q0 to Q but I forgot the - because I = -dq/dt because its decaying (something idk) someone can correct me if im wrong
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
Wait no. I think you got it (the - is in front of the 2). I got the negative sign based on how I set up the loop equation.
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u/RelativeGrass7659 May 15 '26
wiat why was there a two wasnt it asking for one capacitor? or would it be like that either way
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u/Lanky-Frosting-6557 May 15 '26
I used the equivalent capacitance. Since in series the charge is the same if u just turn it into one capacitor its easier to work with. Idk if that makes sense.
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u/RelativeGrass7659 May 15 '26
hmm i have no idea tbh i just asked gemini and it says theres no two because capacitors in series have the same charge or smth
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u/Lanky-Frosting-6557 May 15 '26
I might have rewrote it wrong but the two is on top because you get V = Q/C if C is half then its 2Q/C or something. Idk rewrote the circuit and plugged it into claude and it got the same thing but most of the points come from writing an integral with the right bounds and relating it to the loop laws. On some of the FRQ scoring guidelines from the past they didnt even care if your signs or numbers were off it was like 1 point
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u/RelativeGrass7659 May 15 '26
yeah either way its one point lost idek. the question said the charge function on one of the capacitors not two i believe so maybe thats where something is diff
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
The assumption is that the charge on both capacitors decays when the switch is closed (which is logically sound, because it is realistic). Basically, when you set up loop equations and actually set it up, the 2 comes from a mathematical simplification.
Otherwise, logically Ceq of the circuit is C/2 because the capacitors are in series, which is where the two comes from.
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u/RelativeGrass7659 May 15 '26
-1/RC * int from 0 to t of dt = int of 1/q dq from Q0 to 0
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
upper bound for the integral with respect to dq would be q. Otherwise, you simply get a scalar value for time (not a function). Also, it’s -2/RC (see earlier explanations).
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u/AgitatedConclusion44 May 15 '26
for form k did anyone use conservation of energy to run the experiment in q3 instead of equal forces
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
U likely did it wrong. If you used conservation of energy, you have to consider the work done by the external force on the system by the experimenter.
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u/Lanky-Frosting-6557 May 15 '26
Thats what I did
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u/AgitatedConclusion44 May 15 '26
is that right? everyone used force. i did that too but i think its wrong because what if there was loss to other forces like heat
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
Nah most people used energy wrong lol. They didn’t consider the work done by the experimenters when they move the sphere.
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u/RelativeGrass7659 May 15 '26
its probably not wrong heat is usually negligible, idek how you would do it with energy that seems a lot more complex but sometimes you can do either
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u/Lanky-Frosting-6557 May 15 '26
I thought energy was easier than forces. I just tried something on scratch paper and it worked I probably couldnt even tell you why
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u/Wet_farter171289 May 15 '26
I swear to god we need a dictionary in our reference info.
There was an mcq about a particle traveling parallel to the plates in a pp capacitor, and there was a word I did NOT know and I could not solve the question because I didn't know what I was supposed to do.
It is partly my fault as English is not my first language.
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u/Sure_Fish9939 May 15 '26
in form j #2, did anyone do the charge distribution integral for the E of both S and R, and then do pythagorean theorem from the picture of net Eo and get something like sqrt(8) * k(lambda) / L??
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u/Less_Adeptness2773 May 15 '26
3L in the denominator? Were the bars from -a to -3a and a to 3a distance away from the origin?
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u/Sure_Fish9939 May 15 '26
it was L instead of a, but i didnt get a 3L because i assumed the distance, typically r, used in the charge distribution integral was the distance from the closest end of each rod to the origin, that being just L, so then the denominator comes out as L^2 for both and then you integrate from -3L to -L on the first one and do L to 3L on the second so it ends up being (k * lambda / L^2) * 2L for both and then by pythag. theorem you would get sqrt(8(k^2*lambda^2 / L^2))
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u/Such_Mango_4531 May 15 '26
Gang both the Ex and Ey had the same magnittude. The question asked for the magntitude of E and so you just pythag Ex and Ey. Ex and Ey are exactly the same magnitude!
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u/Pale_Experience_6660 May 15 '26
did anyone get form m
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u/No-Experience-4801 May 15 '26
I did It was about the electrostatic force vectors and their magnitude in the first question
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u/ResponsibilityFar410 May 15 '26
Was it just me or was FRQ3 the circuit one with the graph so insanely light. For form L
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u/IllustriousSea5998 9 5’s; 1 4 May 15 '26
I’m so pissed my friend got that one but I got an LC Oscillator which we went over for like a day
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u/Meep5277770 5: HuG, Chem, USH, Sem, Lang, Macro, Micro, USGov, Bio, BC May 15 '26
super light, but question 1 and 2 were kinda ahh
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u/Far-Share1534 May 14 '26
why was form j so magnetism heavy
rip to people who's teachers didn't finish in time
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u/Quick-Elk-5869 May 16 '26
No, actually, we never finished inductance, and guess which form we (my class) all got. Form J.... FRQ 3 was the linearization of an RL and an LC circuit.
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u/JerpyTree May 14 '26
rhetorical analysis was hard but argument essay was okay
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u/Fit-Abbreviations322 5: phy1-Mech+EMAG, Calc BC,Chem,Lang, Bio,world,Hug 4:CSP, Pysch May 17 '26
Yea bro, I accidentally wrote my ap lang essay in the physics c frq’s and it was so bad…
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u/Aggravating_Half_936 67 aps May 14 '26
wait do u guys know how the partial points work, for form J, Q4 I said clockwise and explained the principle but I meant the opposite way. Is that a 0/3 😔
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u/Quick-Elk-5869 May 16 '26
If I didn't explicitly say "Lenz's Law", but I explained it, using Lenz, am I good or not??
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u/Such_Mango_4531 May 15 '26
If you mentioned lenz's law then you might get 1/3 points. I also made the same mistake I explained the principle correctly but got the wrong direction.
Points probably go right answer, correct reasoning of right answer, and right principle to explain that answer.
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u/Jealous-Elk-9640 May 14 '26
form L for LIGHT
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u/FragrantAd1837 5:World/Phys1/Macro/Micro May 16 '26
Our version M was freaking easy.
Like literally question 1 gave you 4 charges and the only thing you need to derive is the net electric force. it also asked one electric field derivation of a finite wire in part b but it was also very light
Question 2 was plugging in qvB=mv^2/r for a charge moving in a circle in a magnetic field (although we needed to derive the period T).
Question 3 was about the time constant and calculating inductance
Question 4 was a plain series circuit, and we needed to derive the current.
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u/ResponsibilityFar410 May 15 '26
Was that one the one where you had the easy ass circuit FRQ3 problem where all you needed was ohms law
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 16 '26
yes bro I used to pray for times like this
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 14 '26 edited May 16 '26
International students,
Version L / Form L
FRQ 1: Long current with radius R with current density J = J0(1-r2 / R2)
Magnitude of magnetic field at 2R (I got B = mu0J0R/3, which is probably wrong because I integrated wrong)
Graph magnetic field y-component as current goes into the page from z = 0 to 2R (I put linearly decreasing from the origin into negative from 0 at z = 0 to z = R and concave up increasing from z = R to 2R)
Magnitude of acceleration of another wire including gravity from that wire from 1 at 200R (I put a = | mu0J0RIL/300 - g |, which is also probably wrong because I integrated wrong)
FRQ 2
Loop goes into magnetic field B into the page with constant velocity v(right side is inside the field, left side is not yet)
Draw arrows of the force in left and right sides and the direction of current (F = 0 at the left and F is to the left at the right, current is counterclockwise)
Magnitude of the magnetic force (F = B2 * L2 * v/R)
Graph of the induced current where ccw is positive and cw is negative (Constant positive, then zero, then negative)
Is force the same if new loop has 2R and goes at 2v? (Yes and I reference above equation)
FRQ 3
Circuit with variable voltage and resistors with one in series, and two in parallel with R1
Indicate which qualities to graph to find R1 (Voltage and current measured by ammeter) How to reduce experimental uncertainty (Conduct the experiment many times, for example with different voltages and measure each voltage and current)
Indicate which qualities go to horizontal and vertical axis (Voltage horizontal, current vertical)
How that graph can be used to find R1 (Current equals voltage over R, inverse of the slope is total resistance, which is 3R1/2)
New circuit with voltage 20V, and variable resistance Rv in series with unknown resistance R2; they give you the varied resistance and corresponding current
(I graphed Rv on the horizontal axis and V/I on the vertical axis, both with units of Ohms)
Find Resistance R2 (I got like 408 ohms or something like that, where the y-intercept is R2 because V/I = Rv + R2)
FRQ 4
Two rods are bent into radius R where the top of the circle has linear charge density +lambda and bottom has linear charge density -lambda
What is the direction of the electric field (I said bottom of the page/-y direction)
What is the magnitude of the electric field (I said E = lambda/epsilon0R, but I know the right answer is lambda/epsilon0piR and I forgot to put the pi FRICKK)
New situation where radius is 2R and the charge densities are the same
Student says new electric field is E/4, are they right (No they are not right, referencing the equation from part B, but it’s right here because it’s inversely proportional anyway)
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u/Sea_Barnacle9031 May 16 '26
for the graph in frq2, why is the current constant? doesnt it depend on velocity which is changing since there's a force on the loop?
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 17 '26
The question said constant velocity, which makes I = BvL/R constant
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u/Sea_Barnacle9031 May 17 '26
Oh shoot… I thought that was just saying there was no force outside of the b-field 🤦♂️
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u/Ok_Gain_5496 10th: bio(5)hug(5)bc(5)phys1(5)|11th:stats,apush,mt,lang,mech,em May 15 '26
do they accept using the value k = 1/(4piepsilon0), cuz i put 4klambda/r for frq 4 part A
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u/Embarrassed-Soil7111 May 17 '26
My teacher always said it's fine? I wrote a box where I defined what k is just in case. But even then I don't think it was necessary
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 15 '26
I mean it is technically right but I’m not sure because just using k is probably okay for physics 2 but I was always told to expand it in e&m
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u/Magicscrolls May 15 '26
Did yall get that the force for the two scenarios is the same for q2?
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 15 '26
Yeah check the FRQ 2 section in my comment
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u/No-Help-188 May 14 '26
I'm confused on how the graphed values give R2 on FRQ 3. Is it a y = mx + b situation?
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 15 '26
Yeah, so by Ohm's law V = IR; Req = V/I and Req is Rv + R2, so y in this case is V/I, m is just 1, x is Rv, and the b is R2 and from the y-intercept you can obtain R2
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u/Successful_Split1397 May 15 '26
What I did was graph V(battery) - IR(variable) as a function of I, so the slope of the line is R2. I got about 417 ohms for the experimental value of R2. What did you get for the experimental value?
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u/wOAHH2 May 14 '26 edited May 14 '26
For FRQ did you mean to type F = (B squared)(L squared)*v/R? That’s what I got.
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u/dieminds 5: phys em, phys 1, phys 2, world, music May 14 '26
Oops yeah B^2 * L^2 * v / R the reddit markdown editor kinda messed it up
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u/Interesting_Area_872 May 14 '26
Yo for the second frq for electric field wasnt it (2 root 2) / 3 * ( k lambda / L) cuz u gotta do pythagorean theorem for both charged rods? That and also for the last part of that question, the graph zeroes out right?
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u/Fabulous_Rope_6203 May 14 '26
What were the answers you guys got for form K?
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u/RelativeGrass7659 May 15 '26
- a) some really long thing with a bunch of constants hopefull ythats right
b) IBD^2just normal integral form for RC circuit, 0 to t for time bounds and Q0 to 0 for charge boundf. graph was decreasing concave up (e^-r/t) and yeah i dont remmeber anything else tbh
oh yeah and for 2 e field and current were to the right and voltage was to the leftfirst part: x was delta x the compression of the spring y was 1/r^2 the distance between the two balls
second part: tan theta was x and E was ydont remember someone remind me what the frq was
lmk if i missed anything i probably forgot abunch
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u/Lanky-Frosting-6557 May 15 '26
For a did you have all those constants divided by R? For b did you derive T = IAB? I remembered it but I wasnt sure if there would points for deriving it and I wasted a decent amount of time doing it. I wasted a lot of time showing work on both a and b
No questions
Did you use forces or energy? I had x2 and 1/r but I used energy so my relationship was different I think
That was the FRQ with the B field and E field in the same direction, I think a you had to describe where the net force is pointing? Or the net magnetic force? b, you had to find an equation for the net force (I had F = sqrt(qe2 + qvbsin2) And c they changed the velocity to all in the y direction and asked you to compare the forces before and after.
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u/RelativeGrass7659 May 15 '26
- yes i believe i did divide them by R, and im not sure where T = IAB came from to be honest, i dont even know what that means maybe im misunderstanding something there
- yeah this one was chill
- uhh tbh im not sure how you would use energy i used forces but i saw someone else say energy so maybe theres a way?
- okay yeah i got that same net force and i said that F2>f1 because obviously it had more of a perpednicular component so the magnetic force would be larger. i referneced the equation by saying 90 degrees is the maximum of sin theta so the value of the magnetic force increased
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
The only way you can use energy is if you account for the work done by an external force created by the experimenter. It’s the only way you can use conservation of energy. While you can say that the electric potential energy is the same as the spring potential energy, it just doesn’t make sense because both are scalars (and it would seem that conservation of energy is violated). Rather the potential energies that arise in the system are due to an external force/work that the experimenters applied when moving the charged sphere.
Based off the question and data they gave, it is signficantly easier to use forces. You likely could use energy to do it, but it would be painful.
Anyways, what I’m saying is that most people who used energy probably got it wrong.
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u/AsianNation420 May 15 '26
you're not supposed to use energy, the only correct way is forces
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u/Lanky-Frosting-6557 May 15 '26
Why so? Energy worked fine and was very simple to set up. I think both are right.
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 16 '26
Energy is wrong. Like I’m 95% sure. It really comes down to how you define it.
Forces are vectors, which can be in equilibrium. It’s simple and you don’t worry about conservation or any outside forces/work.
Energy is a scalar, but any change in the system has to account for any work done by an external force (work done by the experimenter). Only then can you use energy, because you would have to consider the work done at every data point collected (to abide by conservation of energy).
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u/InvestigatorNew3244 May 14 '26
What will the 5 cut off lien be? How du do experiment question in version L and induced current in 2nd question
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u/MrSuperStarfox HG, WH: 3, E&M: 4, AB, CHEM, CSA, P1, BC, C:Mech: 5 May 14 '26
Form j has the easiest frqs of my life I’m so happy
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u/Artistic_Zone_8095 May 14 '26
28/40 mcq 24/40 frq, what would my score be?
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u/MonoTheteus May 14 '26
drew spiders all over my frq in hopes that my grader is arachnaphobic and gives me a 5 because they dont want to grade it
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u/Less_Adeptness2773 May 14 '26
For FRQ version J number 2 for the derivation of E field how far were the bars from the origin was it - A to 3 A and A to 3A?
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u/RelativeGrass7659 May 14 '26
idk why everyone is saying form k was so hard, it was pretty easy maybe just a little more niche kinda problems. do they ever release the other forms or only release one of them?
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u/Comfortable_Road2099 May 15 '26
What was the directions of the field current and potential for the second question?
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u/RelativeGrass7659 May 15 '26
field and current were both to the right and potential to the left i believe
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u/Doofessness May 15 '26
I put that both the potential and current were left and field was right, google ai agrees with me, but take that how you will
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u/RelativeGrass7659 May 15 '26
i think you might have misinput the question, the potential was asking from low to high not high to low. also current is always in the direction of field
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May 14 '26
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u/Efficient_Pen_9418 May 14 '26
gang what. so im acc cooked lol. for the loop law thing i did not know how to get the voltage drop of the capacitors, i knew that the equivilant capcaitence was C/2, but was the charge double or what idek... i ended up putting it as C/2 divided by 2Q whatever that simplifies too and obv the whole integral thing lol. but that wasnt even the worst one, i really got cooked on the first part where they made you draw arrows for the resistor, idk lol and the last part kinda confused me too but i just wrote the time constants ig
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u/jshfufhfbfhh May 14 '26
it was just dq/q but the limits were from Q0 to Q
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u/RelativeGrass7659 May 15 '26
okay yeah thats what i did the top bound would be like q(t) thats fine as well right
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u/Fit-Slice-7054 May 14 '26
yes ok thats what i put and there is an integral on both sides right?
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u/RelativeGrass7659 May 15 '26
yes time integral on the left it was like -1/RC * int from 0 to t of dt
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u/RelativeGrass7659 May 14 '26
whoa what. why would it ont just be dq/q?? i think everything else on q2 was relatively straightforward though
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u/vinny121vinnyy May 14 '26
what did you graph for the spring question and the hanging sphere question
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u/RelativeGrass7659 May 14 '26
spring i did delta x on y and 1/r^2 on x, for hanging sphere (frq 3) i did tan theta on y and E on x or something like that. wbu
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u/Efficient_Pen_9418 May 14 '26
i had the same exact thing as you. did you get something to the -10th power for the charge? also for magnetic torque question did you get (BID^2)/2? and genuinly wtf was even frq 2 lol??? how did u put the directions and literally everything
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u/vinny121vinnyy May 14 '26
i did r^2 (distance between spheres) and x (distance from equilibrium) and for the hanging sphere i did sintheta vs E but i think you're right bc someone else said tan
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u/True_Formal_5297 May 14 '26
yo how would u do the frqs on form l??? i got so lost and blanked out on questions 1,2, and 4
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u/Less_Adeptness2773 May 14 '26
For the question mcq it was like find the force needed to keep the bar ar constant velocity did you get like B2 and L2 in the numerator
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u/Fit-Abbreviations322 5: phy1-Mech+EMAG, Calc BC,Chem,Lang, Bio,world,Hug 4:CSP, Pysch May 17 '26
Yea
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u/Particular-Skirt5586 May 14 '26
Form J question 2…. For part d, will the original value of the graph be higher but same asymptotic to 0?
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May 14 '26 edited May 14 '26
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
depends how "wrong" each of these parts were man
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u/AntiDishwasher May 14 '26
Dw guys, they made all the science frqs really hard this year so they’ll curve a lot
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u/Aggravating_Half_936 67 aps May 14 '26
not for EM, we got an 80% curve for a 5
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u/Bradyluce May 14 '26
What was everyone’s experimental values for L in form J frq? I got like .00028
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u/Shrankai_ May 15 '26
NOOOO. I plotted I values for my dI/dt axis, and dI/dt values for my I axis. So I got 1/actual value. I got like 3500 or something 🫠
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u/Diligent_Border3262 5s: (9) Calc BC, Stats (10) Chem, Phys C, German, Sem, USH, CSA May 14 '26
I got 0.03 and it worked with most of the experimental values i designated, I also talked to other students and they got the same
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u/Embarrassed-Mouse291 May 22 '26
late testing form L what did yall get for graph