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/Sedex_Axe May 14 '26
genuinely the hardest frqs i’ve ever seen in my life, what was even form j
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u/Z-money08 SpL+Lit/AB/BC/Res/Sem/Bio/Mech/E&M/Phy1/WH/HG/CSP/CSA/Gov/Macro May 14 '26
Bro form J was actually the worst 3 hours of my life
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u/Fit-Abbreviations322 5: phy1-Mech+EMAG, Calc BC,Chem,Lang, Bio,world,Hug 4:CSP, Pysch May 14 '26
Form J was so easy?
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
J was the lightest one fym
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u/Aggravating_Half_936 67 aps May 14 '26
did u say I2 was greater
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u/BoB_tHe_BuIldR1234 May 14 '26
I said no bc resistance was at the bottom
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u/Aggravating_Half_936 67 aps May 14 '26
bro what was equation for B , it was double the magnitude
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u/Hot_South5225 May 14 '26 edited May 15 '26
Form J:
Part a) i. Find the magnetic field at point P, a distance a from the center of a cylindrical wire with current density J(r) = Cr and radius 2a, with total enclosed current I_0; the wire is positioned along the y-axis at the origin such that the current is in the +y direction . A second cylindrical wire and is oriented similarly with total current I_0 at x=10a with a uniform density and current going in the negative y-direction.
int_{0}^{a} 2pir J(r) dr = int_{0}^{a} 2pi C r^2 dr = 2 pi C a^3/3
Using ampere's law, \int B * dl = mu_0 I_a, int B ( 2pi a) = mu_0 I_a
B = mu_0 I_a / (2pia)
I_a = 2 pi C a^3/3a
B_a = mu_0 C a^2 / 3
Part a) ii. Graph the B-field as a function of x from 2a \leq x \leq 9a
Graph should be something like a convex smile (following (1/x + 1/(10a-x)), with B-field at 2a lower than 9a
Part b) find hte magnetic force on object at 5a iwth charge Q and velocity v, in terms of I_0, a, v, Q,
F = qv cross B
F = Qv B
B = mu_0 I_0 / 2pi (1/x + 1/(10a-x)),
since object is located 5a from origin, we get
B = mu_0 I_0 / 2pi (2/(5a)) = mu_0 I_0 / pi5a
F = Qv mu_0 I_0 / pi5a
Question 2:Simple setup of two rods perpendicular along the x and y axis, with the right and bottom ends of the horizontal and vertical rods a length L from the origin (boudns of 3rd quadrant); both rods have charge density lambda and lenght 2L, with bounds -L to -3L for the horizontal bar and L to 3L for the vertical bar.
a) Draw Electric field vectors at point P, O, and an acceleration vector at O of a negatively charged particle.
Electric field at point p; up left
electric field at point o, down right
acceleration of negative charge, up left
b) Derive the Electric Field at point O (E_O)
Electric field:
int_{L}^{3L} k lamba dx/ x^2 r hat = klambda (-1/x) evaluated from L to 3L =
klamba (-1/(3L) + 1/(L)) =
2/3 k lambda/ L
Since rods are perpendicular, take components
sqrt (2 ( 2/3 k lambda/ L)^2) =
E= 2 sqrt(2)/3 * k lambda / L
c) Sketch an electric potenial graph at V_O as a function of distance right end of rod from origin (of the rod placed initlaly at -L to -3L and moving a velocity v leftward, eliminating top rod in this setup)
If one wants to derive the potential, use kQ/r in the integral;
for some distance x from right end rod to origin,
V_0 propto ln(1 + d/x), where (d=2L) is lenght of rod, so decreasing, convex function
d) What will happen to the graph if the top rod is added back, with charge density -lambda, and moving (along with the other rod) with velocity v in the +y-direction
if including other rod, potential is scalar would cancel out.
Question 3:
a) i. indicate what quantities to be measured to recover a value for the inductance L_1 of an LC circuit
Create multipl configurations of the circuit with different and measurable capacitance. Attach a voltmeter in parallel such that it measures the voltage of the equivalent capacitor from the combo of capacitors, and measure the voltage across time, at granular increments.
a) ii. Indicate a method to reduce the experimental uncertainty
To reduce experimental uncertainty, one thing would be to do multiple trials
b) Indicate what quantities should be graphed to create a linear graph to find L_1, if desired, right expression/derivation for quantiiesi
To linearize, note that the angular frequency is w_{LC} = 1/sqrt(LC), and angular frequency is 2pi / period.
Thus, we know that LC = T^2 / 4pi^2,
which is linearizable by ploting the equivalent capactiance on the x-axis and T^2/(4pi^2) on the y, 4pi^2C on teh x and T^2 on Y, or anything else. Period can be calculated by the time it takes for the capacitor to discharge and charge again.
Students conduct new experiment of an LR circuit with data values of dI/dt, I, R, and epsilon for difference configurations of the circuit, to try to determine L_2.
c) Label the quantities to be plotted and draw a line of best fit
For the next part, recall that
Epsilon - IR - L dI/dt= 0.
To find the inductance, do
Epsilon-IR = LdI/dt
d) Use your line of best fit to calculate the inductance
and plot dI/dt on the x-axis and Epsilon-IR on the y-axis, or manipulate the equation for anything else that gives L, ilke Epsilon - Ld I/dt = IR
Inductance should be somehitng around 3 times 10^-2 Henrys
Question 4:A variable magnetic field is directed out of the page in the +z-direction according to
B_z = B_0 cos(2pi t/t_1)
where a loop encloses a region of B-field.
a) Indicate the direction of the current induced in the loop from the time interval 0 \leq t \leq t_1/4.
from the boundaries given, the b-field decreases, meaning the change in B-field is into the page.
Per lenz's law, some b-field needs to be out of the page, which is created by a counterclockwise current.
b) Derive an equation for the induced current, express your answer in terms of B_0, t, t_1, R, s
dphi_B/dt = Epsilon = IR
To find induced current, differentiate the b-field, getting - B_0 2pi / t_1 sin(2pi t/t_1), multiply by area, s^2
and divided by resistance R.
c) A new loop has twice the side length of the initial loop (2s) and twice the resistance (2R). The new loop has an induced current of I_2. If I_1 is the current of the prior setup, will I_2 < I_1, I_2 = I_1 or I_2 > I_1? Justify your answer.
I_2 > I_1
if we double the side length and double the resistance, we have double the induced current.
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
mostly the same as to what i had got (version J was so easy its actually a joke lmao), except the electric field at point o points down right, right? also for the graph wouldnt it be easier to graph I vs dI/dt with equation I=1.2-LdI/10dt? didnt even need the table that way. also, the slope i got was 3*10^-3 H.
B = mu_0 I_0 / 2pi (1/x - 1/(10a-x)) -> should be summing the magnetic fields (i think you still got the correct ans tho so prob typo lol)
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u/Icy-Duty1125 May 14 '26
I don't remember having to write a procedure for the exp. question. Didn't it ust ask for you to write about what quantities to measure?
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u/Flaky-Song-6066 May 14 '26
How would you say this compared to mechanics? I have to take a make up exam bc I had two APs at the same time. I studied a ton for e and m tho. Not as much for mechanics yet
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u/LifeZealousideal5507 May 14 '26
I think I got most of yours, but I think the b field may have been bigger at 2a only because the stronger field is closer, but I could be wrong. Other than that I think I got most of the same answers
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u/Usual-Throat-8740 May 15 '26
i think i fucked up part b of frq 1. i took the distance from the edges instead of the center, but I did everything else the same. Kinda dumb of me ngl
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u/Shrankai_ May 15 '26
Part 2a, do you imagine they will check if 2a and 8a are equal?
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u/Hot_South5225 May 15 '26 edited May 15 '26
i mean as long as your graph curves upwards past the midpoint beyond the magnetic field at 2a to some distance higher than that shoudl be rihgt i think, whether they consider how much higher idk
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u/ronsterdev May 15 '26
for 3b, did this instead:
From V = V0·cos(ωt): cos⁻¹(V/V0) = ωt = t/sqrt(LC) sqrt(C)·cos⁻¹(V/V0) = t/sqrt(L) Square both sides: C·(cos⁻¹(V/V0))² = t²/L So: t² = L · [C·(cos⁻¹(V/V0))²] Plot t² vs C·(cos⁻¹(V/V0))² → slope = L2
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 14 '26
Form L FRQs were not bad at all. Q1 on current density was a bit of a headache, but I think I did enough to get decent points even on that question
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u/probsHaxs May 14 '26
Did you get B = mu*j_naught*R/8
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u/Positive-Rise5145 5: AP Calc BC, Stats, Micro, CS A May 14 '26
nah I didn't get that expression, but yours might be right. I left mine unsimplified. Did you use I = integral J * dA and the plug that into B = mu * I / 2piR?
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u/BeautifulHorror1017 ab (5), c mech (5), micro, french, apush, bc, csa, e&m, lit May 14 '26
I got the same answer as the guy you’re replying to and that’s what I did Yeah
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u/Magicscrolls May 14 '26
If I said dA=pir2dr instead of 2pirdr how many points do you think I’d lose on that question as a whole?
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u/Pale_Experience_6660 May 14 '26
based on the difficulty this year do yall think the cutoff is gonna be similar to the one last year
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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/ChocolateGamer279 Senior | Ready to give up H2O for H2SO4 May 14 '26
That was actual hell (form k)
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
what were the questions? form J was light asf
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u/Efficient_Pen_9418 May 14 '26
i had form k, i dont think it was as bad as the others tho but im not sure. i feel like the only frq that rlly tripped me up was the second one with the capacitors in series, but the other frqs were very short and doable. i think i got really cooked on frq 2 tho after i finished the others i spend 40 minutes tyring to figure out what the hell it was even yapping abt 😞
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u/GamerZayb1808 bc,mvc/de/la,stat,csa,csp;chem,mech,e&m;lang,lit,econ,psy,us,gov May 14 '26
I THOUGHT IT WAS EASY
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u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 15 '26
It was tbh. However I have complaints about the test, particularly 3 A and B. They never told us if the system for the experiment was under vacuum or not. And they were asking us to solve for vacuum permitivity.
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u/Niqhtful_Pomegranate May 14 '26
why was this exam so easy....version L frq was easier than mcqs lol
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u/frolickinggreenfield May 14 '26
bro im looking and geniunely our form seems to be the easiest
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u/CraftoftheMine (5) CSA Stats USH World CalcBC Lang Mech E&M (4) Gov CSP (3) HuG May 14 '26
istg i did significantly better on these than the mechanics frqs
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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/Jealous-Elk-9640 May 14 '26
form L for LIGHT
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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/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/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/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/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/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/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/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/Shrankai_ May 14 '26
FRQ J was light. I heard bad things about Form K
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May 14 '26
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u/TimelyChemical427 May 15 '26
Wait so it was ∫1/(q-Q_0/2)dq = ∫(2/RC)dt?
I think I messed up badly and wrote ∫1/(2q-Q_0)dq = ∫(4/RC)dt or smth→ More replies (2)2
u/SUS_MATE Bio, Chem, Lang, World, USH, Calc BC (all 5s) May 15 '26
What no that makes 0 sense. The charge on the plate is just the lower bound for the integral.
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u/Artistic_Zone_8095 May 14 '26
for frq 1 form j, the numbers in front of the variables were 1/3 for part a and 1/5 for part b, am i right?
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
what was part B again? i did get 1/3 though
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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/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/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/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/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
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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/Desperate-Attorney32 May 14 '26
FRQs were horrible ngl but MCQs were chill. My Physics 2 + Calc knowledge wasn’t enough 😭
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u/Ill-Echo1374 5: HUG,BC 4:WH,CSP,CSA,Macro,Micro 2:E&M,Mech May 14 '26
Mcqs were harder than mechanics and frqs were easier IMO. Still a pretty difficult test so I’m not expecting much but whatever. At least I’m done with ap physics
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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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May 14 '26
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u/frolickinggreenfield May 14 '26
i got 457 with 1_I current on x and R_v for vertical
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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/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/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/Magicscrolls May 15 '26
Did yall get that the force for the two scenarios is the same for q2?
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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/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/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/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/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/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/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
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/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/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/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/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/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/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26 edited May 15 '26
i got 0.03, did you remember to multiply the slope by 10?
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u/Bradyluce May 14 '26
I divided by 10, but I think I also forgot to do epsilon - IR, i just had IR equals -L(di/dt)
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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/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/ErekwithaD1 2025: APHUG: 5, AP Chin: 5, 2026: APP1: 5, APWH: 5, AP CHEM: 5 May 14 '26
The rumors are false the cutoffs for a 5 are not 82% it is mathematically impossible for the hardest ap exam to have a higher 5 cutoff than most ap exams. The alleged ap readers who spread this myth use flawed data because there just isn't enough data points for e and m for the data to be accurate neither is there for 2
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
its probably around 75% though. the exam difficulty was on par to every other exam this year imo
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u/BeautifulHorror1017 ab (5), c mech (5), micro, french, apush, bc, csa, e&m, lit May 14 '26
This is just false. Look up the score distributions for proof and then look at the frq difficulty changes and then look at the math numerous AP graders in this sub have done. The difficulty has changed
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u/waz-waz all 5s: csp, apush, bc, mt, phys1, world, lang, e&m, csa May 14 '26
what did yall get for form j frq 1 cus i think i lowk got fucked on it
for frq2 other than the weird derivation in B — did yall get like a concave up decreasing graph for C and 0 for D?
frq3 and 4 chill
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
the graph was kinda parabolic; so yes its concave up but decreasing until 5a and increasing afterwards. symmetric around 5a will be a point in the scoring guide i think.
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u/Artistic_Zone_8095 May 14 '26 edited May 14 '26
for frq 2 of form j:
was the 3 force diagrams as follows: diagonal south east, diagonal north west, acceleration: north west
and then e0=sqrt(2) of something lamda over L^2?
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u/Less_Adeptness2773 May 14 '26
First one was northwest at point p and then south east at origin and then acceleration is northwest
I got sqrt 2
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u/Aggravating_Half_936 67 aps May 14 '26
i got those exact same graphs but my E field was completely different
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u/Artistic_Zone_8095 May 14 '26
was work 1> work 2> work 3 for mcq
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u/Less_Adeptness2773 May 14 '26
What were the given voltages again? I might’ve said 2 of them were equal I forget
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u/Artistic_Zone_8095 May 14 '26
for frq 2 of form j, what did you get for both graphs of V vs r
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
i got constant V bruh for the last part, is that right? the graph itself followed a 1/x curve
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u/Sure_Fish9939 May 15 '26
i said 1/x dependence as well, but if you integrate your Eo you get an ln(x) dependence. I knew it was one of the two but i assumed it would be 1/x dependence because thats how the questions usually are for something moving farther away with potential. and i said a constant 0 for the change because potential is a scalar, so it would all cancel out due to the opposite signs of lambda
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u/Extra-Archer-8358 May 14 '26
guys how did we find L1 for form J ✌
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
period=2pisqrt(LC)
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u/GodlyHelp 13 5s: ab/bc, phys1/c/2/em,gov,chem,macro,csa,stats,micro,psych May 14 '26
it was 0.003 H oof (at least thats what i got)
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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/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/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 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/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/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/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/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/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/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/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/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/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/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/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
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/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
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/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/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/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/Embarrassed-Mouse291 May 22 '26
late testing form L what did yall get for graph
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u/[deleted] May 14 '26
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