AP Physics C: Electricity and Magnetism
One lesson for each of the course’s 31 topics, in the order the course teaches them. The first 3 units are free for everyone; the rest come with the AP Physics C: Electricity and Magnetism plan. Read a lesson, try its quick checks, then practice the topic with exam-style questions.
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Electric Charges, Fields, and Gauss's Law
- 8.1Electric Charge and Electric ForceUse Coulomb's law to find the size and direction of the force between point charges, add forces from several charges, and compare electric force with gravity.
- 8.2Conservation of Electric Charge and the Process of ChargingExplain how objects become charged by friction, contact, polarization and grounding, and use conservation of charge to track where every coulomb goes.
- 8.3Electric FieldsFind the electric field as force per unit charge, add the fields of point charges, read field maps and field lines, and describe fields of charged conductors.
- 8.4Electric Fields of Charge DistributionsFind the electric field of a charged rod, line, ring or arc by integrating point-charge fields over the charge and letting symmetry cancel components.
- 8.5Electric FluxCalculate the electric flux through flat, curved and closed surfaces, with its sign, from a dot product or a surface integral of the field.
- 8.6Gauss's LawUse Gauss's law to relate flux to enclosed charge, find enclosed charge from a density, and derive E for spherical, cylindrical and planar charge.
Electric Potential
- 9.1Electric Potential EnergyFind the electric potential energy of two or more charges as the work needed to assemble them, and read its sign and its graph against separation.
- 9.2Electric PotentialFind the potential of point charges and charged objects, get potential from field and field from potential, and read equipotential maps.
- 9.3Conservation of Electric EnergyUse the change in potential energy across a potential difference and energy conservation to find speeds, stopping points and energy changes of moving charges.
Conductors and Capacitors
- 10.1Electrostatics with ConductorsExplain why a conductor's charge sits on its surface, why E is zero inside and normal to the surface, and how induced charge and shielding work.
- 10.2Redistribution of Charge Between ConductorsPredict how charge divides when conductors touch or are joined by a wire, what grounding does, and how to charge a conductor by induction.
- 10.3CapacitorsDefine capacitance, derive C and the field for parallel-plate, spherical and coaxial capacitors, find stored energy, and track charges moving between plates.
- 10.4DielectricsExplain how an insulator between capacitor plates polarizes, weakens the field and raises capacitance by κ, and predict changes with or without a battery.
Electric Circuits
- 11.1Electric CurrentDefine current as dq/dt, connect it to drift velocity and current density, integrate a nonuniform J, and give current its direction.
- 11.2Simple CircuitsRead and draw circuit schematics, find every loop, and tell closed, open and short circuits apart, including where ammeters and voltmeters go.
- 11.3Resistance, Resistivity, and Ohm's LawFind a resistor's resistance from its material and shape, integrate a varying resistivity, apply Ohm's law, and read resistance off an I-V graph.
- 11.4Electric PowerDerive P = IΔV, choose between I²R and ΔV²/R, track energy into and out of circuit elements, and rank bulb brightness by power.
- 11.5Compound Direct Current CircuitsReduce series and parallel resistor networks, account for a battery's internal resistance, and predict how ammeters and voltmeters affect a circuit.
- 11.6Kirchhoff's Loop RuleUse energy conservation to write Kirchhoff's loop rule, track potential around a circuit with correct signs, and sketch and read potential-versus-position graphs.
- 11.7Kirchhoff's Junction RuleApply charge conservation at circuit junctions, combine the junction and loop rules to solve multi-branch circuits, and test the rule with ammeter data.
- 11.8Resistor-Capacitor (RC) CircuitsCombine capacitors in series and parallel, derive and solve the RC charging and discharging equations, and use the time constant and steady-state rules.
Magnetic Fields and Electromagnetism
- 12.1Magnetic FieldsMap a magnetic field with poles and field lines, use Gauss's law for magnetism to show its lines always close, and explain magnets, materials and permeability.
- 12.2Magnetism and Moving ChargesFind the magnetic field a moving charge makes and the force a magnetic field exerts on one, with cross products, and analyze crossed fields and the Hall effect.
- 12.3Magnetic Fields of Current-Carrying WiresUse the Biot-Savart law to find the magnetic field of wires, arcs and loops, and calculate the force a magnetic field exerts on a current-carrying wire.
- 12.4Ampère's LawUse Ampère's law with a well-chosen loop to find the field of wires, thick conductors and solenoids, and explain Maxwell's addition to the law.
Electromagnetic Induction
- 13.1Magnetic FluxCalculate the magnetic flux through a loop, with its sign, from a uniform field with the dot product or from a nonuniform field with a surface integral.
- 13.2Electromagnetic InductionUse Faraday's law to find the emf induced by a changing magnetic flux, Lenz's law and the right-hand rule to find its direction, and the induced electric field behind it.
- 13.3Induced Currents and Magnetic ForcesFind the magnetic force on a loop or rod carrying induced current, and use Newton's second law to predict its motion, including terminal speed.
- 13.4InductanceExplain why a coil resists changes in its own current, derive a solenoid's inductance, and compute the emf across an inductor and the energy it stores.
- 13.5Circuits with Resistors and InductorsAnalyze LR circuits just after a switch moves and long after, derive and solve the loop equation, and use the time constant L/R to find currents and times.
- 13.6Circuits with Capacitors and InductorsUse energy conservation to find the maximum current in an LC circuit, derive its oscillation equation, and calculate its angular frequency and period.
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AP Physics C: Electricity and Magnetism questions
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