AP Physics C Units 2027: Complete Mechanics + E&M Map
AP Physics C is two separate calculus-based courses and exams. Mechanics contains Units 1–7 and Electricity & Magnetism contains Units 8–13, for 13 units and 72 current instructional topics across the complete Physics C sequence.
Units 1–7 belong to AP Physics C: Mechanics. Units 8–13 belong to AP Physics C: Electricity and Magnetism. The numbering continues across the two courses, but each course has its own exam, unit weighting, formula emphasis, and practice history. If you are taking only one Physics C course, use only that branch of this map.
AP Physics C: Mechanics
Motion, forces, energy, momentum, rotation, rotating systems, and oscillations. The fastest route through the course is model-first: describe motion, identify interactions, then choose force, energy, momentum, rotational, or oscillatory methods.
AP Physics C: Electricity & Magnetism
Electrostatics, potential, conductors and capacitors, circuits, magnetic fields, and induction. The course repeatedly moves from source → field → potential/energy → force or circuit response, with calculus and symmetry deciding which method is efficient.
Mechanics · Units 1–7
Published ranges describe the approximate share of the multiple-choice section. They are review-priority signals, not a license to skip a lower-weight prerequisite.
| Unit | Content | MCQ weighting | Study emphasis |
|---|---|---|---|
| 1 | Kinematics | 10–15% | Foundation for every later mechanics model |
| 2 | Force and Translational Dynamics | 20–25% | Foundation for every later mechanics model |
| 3 | Work, Energy, and Power | 15–25% | Use calculus with conservation, rotation or oscillation models |
| 4 | Linear Momentum | 10–20% | Use calculus with conservation, rotation or oscillation models |
| 5 | Torque and Rotational Dynamics | 10–15% | Use calculus with conservation, rotation or oscillation models |
| 6 | Energy and Momentum of Rotating Systems | 10–15% | Use calculus with conservation, rotation or oscillation models |
| 7 | Oscillations | 10–15% | Use calculus with conservation, rotation or oscillation models |
Electricity & Magnetism · Units 8–13
E&M starts at Unit 8 because the Physics C numbering is continuous even though E&M is a separate course and exam.
| Unit | Content | MCQ weighting | Study emphasis |
|---|---|---|---|
| 8 | Electric Charges, Fields, and Gauss's Law | 15–25% | Foundation for fields and potential |
| 9 | Electric Potential | 10–20% | Build from fields, potentials and conservation |
| 10 | Conductors and Capacitors | 10–15% | Build from fields, potentials and conservation |
| 11 | Electric Circuits | 15–25% | High-value circuits and differential models |
| 12 | Magnetic Fields and Electromagnetism | 10–20% | Build from fields, potentials and conservation |
| 13 | Electromagnetic Induction | 10–20% | Build from fields, potentials and conservation |
How the units depend on one another
Mechanics: motion → interactions
Unit 1 gives the kinematic language. Unit 2 supplies force models. Units 3–4 provide energy and momentum alternatives. Units 5–6 extend the same ideas into rotation, and Unit 7 adds oscillatory differential-equation reasoning.
E&M: field → potential → matter
Unit 8 establishes charge and electric field. Unit 9 turns field into scalar potential/energy. Unit 10 applies electrostatics to conductors and capacitors before Unit 11 builds circuit dynamics.
Magnetism → induction
Unit 12 introduces magnetic fields and force laws. Unit 13 then asks what changing magnetic flux does to electric fields, currents, forces, inductors, LR circuits, and ideal LC oscillation.
Weighting should change review order—not learning order
High-weight Mechanics review
Unit 2 (20–25%) and Unit 3 (15–25%) deserve substantial mixed practice, but both rely on Unit 1 representations and calculus. A weak kinematics model can still sink a high-weight dynamics problem.
High-weight E&M review
Units 8 and 11 each carry 15–25% ranges. They are high-value review areas, yet circuit and magnetism problems still depend on potential, field, charge, and calculus foundations.
Ranges are not exact question counts
The published percentages are ranges for the multiple-choice section. Do not convert a range mechanically into a promised number of questions on your individual exam form.
FRQs are skill-integrated
The four free-response task types can combine content with calculus, representations, experimental design, and written justification. Unit weight alone does not predict which skill will dominate an FRQ.
Four ways to use this 13-unit map
First learning
Follow the course sequence and do not skip prerequisite units. Open each unit’s first lesson, then move topic by topic.
Formula review
Use the formula library beside the unit map. For each relationship, identify the unit, model conditions, units, and calculus connection.
Weakness repair
Route every practice miss back to one unit and one topic. Relearn the model before solving a parallel question.
Final review
Mix units according to current weighting ranges while preserving enough breadth that low-frequency prerequisite ideas remain retrievable.
Science practices run through every unit
Creating representations
A unit is not mastered if you can only manipulate equations. You should be able to create or interpret free-body diagrams, motion graphs, energy or momentum representations, field maps, circuit schematics, flux surfaces, and experimental graphs where appropriate.
Mathematical routines
Calculus is integrated throughout Physics C: derivatives describe rates, integrals accumulate physical quantities, and differential equations connect force or circuit laws to time evolution. The specific mathematics changes by unit, but the habit of translating physics into mathematics does not.
Scientific questioning and argumentation
Labs and data tasks require more than plugging numbers into a formula. You need measurable variables, a defensible procedure, graph or fit choices, uncertainty reasoning, and a claim supported by data.
Cross-unit synthesis
Strong exam problems often feel difficult because they require selecting among several familiar models. Train by asking which unit supplies the governing principle and which earlier unit supplies the representation or calculus tool.
Common unit-map mistakes
Counting units instead of topics
The 13 unit labels are broad containers. Physics C currently contains 72 instructional topics in this build, so a unit-level checklist alone is too coarse for diagnosis.
Treating weight as difficulty
A higher MCQ weighting range does not mean every problem from that unit is harder. Weighting describes representation on the section, not the cognitive difficulty of an individual question.
Skipping bridge concepts
Mechanics ideas such as energy, momentum, torque, and oscillation can reappear as reasoning patterns in E&M. Likewise, algebra-based Physics 1/2 foundations can support understanding, but the Physics C lesson must still be learned in its calculus-based form.
Find the correct starting unit without mixing the two exams
Choose what you are taking and the kind of breakdown you are seeing. The router points to the earliest high-leverage repair location while keeping Mechanics and E&M score histories separate.
Six cross-course bridges that reduce duplicated studying
| Mechanics habit | E&M analogue | What transfers | What does not transfer automatically |
|---|---|---|---|
| Free-body/system model | Charge/current/field source model | Define the system and interactions before equations. | Electric and magnetic directions require their own vector rules and source geometry. |
| Potential-energy method | Electric potential/potential energy | Use scalar energy/potential when force integration is inefficient. | Voltage is energy per charge, not mechanical energy itself. |
| Flux/area-style geometric reasoning in labs | Electric and magnetic flux | Area vectors, orientation and integral thinking. | Gauss and Faraday answer different physical questions. |
| Linear momentum ↔ angular momentum | Field/circuit conservation reasoning | Choose conserved/system quantities before algebra. | There is no one-to-one momentum formula substitution for circuit laws. |
| Mechanical SHM differential equation | Ideal LC oscillation | Second-order restoring dynamics, phase and energy exchange. | The stored energy variables are electric and magnetic, not spring/kinetic. |
| Exponential drag/relaxation intuition | RC and LR transients | Endpoint checks and time-constant thinking. | The governing circuit law and physical parameters must be derived independently. |
When you are taking both Physics C courses
Keep two error logs
Use the same error categories—model selection, representation, calculus, sign/unit, experiment, communication, pacing—but keep course/unit labels separate so a Mechanics weakness does not distort the E&M diagnosis.
Reuse mathematical habits
Derivative, integral, differential-equation and graph habits transfer strongly. Reusing the habit is efficient; reusing a special-case formula across domains is not.
Schedule cross-course retrieval
Once both courses are learned, include short bridge prompts such as mechanical SHM vs LC oscillation or force-system conservation vs Kirchhoff constraints. The goal is discrimination, not blending the exams.
Practice full exams separately
The May 2027 exams share the same 42/85 + 4/95 architecture, but they draw from separate unit frameworks. Full simulations must therefore remain course-specific.
13-unit map FAQs
Are there really 13 units on one AP Physics C exam?
No. Units 1–7 are Mechanics and Units 8–13 are Electricity & Magnetism. They are separate AP courses and separate exams.
How many topics are represented across this plugin?
There are 72 instructional topics: 41 in Mechanics and 31 in E&M.
Should a student taking both courses finish all Mechanics before starting E&M?
E&M recommends prior calculus-based Newtonian physics, so Mechanics or an equivalent course is a strong foundation. Local course sequencing can vary, but the two exam frameworks should remain distinct.
Which units deserve the most final-review time?
Use current weighting ranges together with your own error evidence. High-weight units deserve coverage, but prerequisite gaps can have greater cross-unit leverage than percentages alone suggest.
Can I use one 42-question practice test for both courses?
No. A current-format simulation should use 42 questions from the specific course framework being practiced.
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