Stanford PHYSICS 43: Electricity and Magnetism
PHYSICS 43 is the electricity and magnetism quarter of Stanford's introductory physics sequence for engineers and physical science majors: fields, Gauss's law, circuits, magnetism, and induction. Sequence folklore consistently ranks it the hardest of the intro physics courses.
Fennie is independent and not affiliated with Stanford University. This is an unofficial study guide.
What makes it hard
E&M is abstract in a way mechanics isn't: you can't picture a field the way you picture a block on a ramp, and the mathematics (flux, surface integrals, vector fields) is doing more of the conceptual work. Sign errors and direction mistakes (right-hand rules, induced currents) silently wreck otherwise-correct solutions, and the topics chain hard from fields through induction.
What you'll cover
- • Electric fields and Gauss's law
- • Electric potential
- • Capacitance and circuits
- • Magnetic fields and forces
- • Electromagnetic induction
The PHYSICS 43 study guide
How to study for Stanford PHYSICS 43, step by step.
- 1
Invest in the field concept early
Everything in PHYSICS 43 is fields, and students who treat them as formula inputs rather than physical objects struggle all quarter. Spend real time on field-line pictures and what flux means before Gauss's law arrives.
- 2
Master symmetry arguments for Gauss's law
Gauss's law problems are won by choosing the right surface and articulating the symmetry. Practice the argument in words, not just the integral. Exams probe whether you know why it works.
- 3
Drill directions until they're physical
Right-hand rules, force directions, induced-current directions: practice until you reason them physically rather than reciting mnemonics under pressure. Direction errors are the silent grade-killer of this course.
- 4
Keep the chain unbroken week to week
Fields feed potential feeds circuits; magnetism feeds induction. At quarter pace a weak week compounds. Review backward briefly every week so nothing has gone cold when induction stacks it all.
- 5
Practice unfamiliar setups under time
As with mechanics, the exams break homework patterns deliberately. Timed problems from outside sources in the final week before each midterm calibrate you to the real bar.
Today
Today's PHYSICS 43 plan
What a Fennie Daily Plan looks like for PHYSICS 43. Yours is built from your own syllabus and adapts every day to your deadlines and progress.
First plan free, no card required. Fennie is independent and unaffiliated with your school.
FAQ
Is PHYSICS 43 harder than PHYSICS 41?
Most students say yes. E&M's abstractions can't be visualized like mechanics, the vector calculus does more work, and direction/sign errors silently destroy solutions. The students who do well invest early in field intuition rather than formula collection.
How do I study for PHYSICS 43 exams?
Build the physical picture first: field lines, flux, what Gauss's law is saying. Then drill direction reasoning until right-hand rules are physical rather than mnemonic, and practice unfamiliar timed problems. Exams break homework patterns by design.
What math does PHYSICS 43 use?
Single-variable calculus throughout, plus the vector concepts (flux, surface and line integrals at an introductory level) that make E&M expressible. The math isn't deep but it's load-bearing: hesitation with integrals becomes hesitation with physics.