Students and parents preparing for undergraduate study in China and the CSCA physics exam can begin with electromagnetism. Below, drawing on the official syllabus and data from four past papers, we explain how many electromagnetism questions appear on the exam, how the four sections are distributed, which formulas you need to master, and what you should review first.
How Much Electromagnetism Is Tested
The official CSCA Physics Examination Syllabus (2025 Edition) states that the exam lasts 60 minutes and contains 48 single-choice questions worth 100 points in total; the five modules are Mechanics, Electromagnetism, Thermodynamics, Optics and Modern Physics.
We counted four past papers (2025-12-21, 2026-01-25, 2026-03-15, 2026-04-25), totaling 188 questions (four questions were missing). Together, the four electromagnetism sections account for 52 questions, or 28% — second only to mechanics in question count. For students preparing for the physics exam, electromagnetism is not a small part that can be left until the end.
Number of Questions in the 4 Sections (How Many in Each of the 4 Papers)
The four numbers in parentheses follow the order of the four past papers: 2025-12-21, 2026-01-25, 2026-03-15, and 2026-04-25.
- Electrostatics: 22 questions (7, 5, 4, 6) — the largest section within electromagnetism.
- Circuits: 11 questions (2, 3, 3, 3) — the count is relatively consistent across the four papers.
- Electromagnetic induction: 10 questions (1, 4, 4, 1) — there is considerable variation between papers.
- Magnetic fields: 9 questions (3, 2, 2, 2).
These figures show that electrostatics has the most questions and circuits also has a substantial number; although electromagnetic induction is not the largest in total, it varies noticeably from paper to paper, so you cannot plan your review based on the feel of a single paper.
Electromagnetism Scope in the Syllabus
According to the syllabus, the electromagnetism part includes:
- Electrostatics: Coulomb's law, electric field strength, electric potential
- Direct current circuits: Ohm's law, series and parallel circuits
- Magnetic fields: magnetic induction, Ampere force, Lorentz force
- Electromagnetic induction: Faraday's law, Lenz's law
When reviewing, you can first practice these four parts section by section, then practice them together. Each knowledge point listed in the syllabus should be paired with its formula and the basic method for judging when to apply it.
Formulas You Must Know
You must be able to write and use the following formulas, and you must also know the conditions under which each one holds.
- Coulomb's law: F = kq₁q₂/r²; electric field strength: E = F/q
- Ohm's law: I = U/R
- Series resistance: R = R₁ + R₂
- Parallel resistance: 1/R = 1/R₁ + 1/R₂. For example: two 6 Ω resistors in parallel have a total resistance of 3 Ω.
- Electric power: P = UI
- Ampere force: when the current direction is perpendicular to the magnetic field, F = BIL
- Lorentz force: when the velocity is perpendicular to the magnetic field, f = qvB
- Faraday's law of electromagnetic induction: E = nΔΦ/Δt
- Lenz's law: the magnetic field of the induced current always opposes the change in magnetic flux that causes it.
Do not simply memorize the letters in the formulas. When doing questions, first check the conditions — such as "the current direction is perpendicular to the magnetic field" and "the velocity is perpendicular to the magnetic field" — and then decide which formula to use.
Review Suggestions
- Start with electrostatics. With 22 questions, electrostatics is the largest section within electromagnetism. Build a solid foundation first in Coulomb's law, electric field strength and electric potential.
- Circuit questions are good for securing marks. The 11 circuit questions involve only a small amount of calculation. Practice Ohm's law and the series and parallel formulas until you can apply them fluently.
- Practice direction questions more. Use the left-hand rule to find the direction of the Ampere force and the Lorentz force, and the right-hand rule or Lenz's law to find the direction of the induced current. Do not rely on memorized conclusions alone for direction questions; work through them step by step using the current direction, magnetic field direction and direction of motion given in the question.
You can arrange your review order by the number of questions: electrostatics first, then circuits, then magnetic fields and electromagnetic induction. Alternatively, adjust the order to suit your own weaker sections. After finishing each section, use the matching questions to check that you can apply the formulas and determine directions.
Next Step
CSCA.PRO's physics section offers a 15-minute diagnostic and knowledge point learning. You can take a test first, then practice section by section.