Moving Charges and Magnetism
Magnetic force on charges and currents, Biot–Savart and Ampere's law, fields of loops and solenoids, the cyclotron and moving-coil galvanometer — a formula-dense chapter that returns 2–3 questions every year.
Is NCERT enough for Moving Charges and Magnetism in JEE?
NCERT covers the Biot–Savart law, Ampère's law, the Lorentz force and the moving-coil galvanometer adequately for JEE Main. Add charged-particle helical motion and field-of-arc or field-of-loop combinations from previous-year papers.
Common JEE questions on Moving Charges and Magnetism
- What is the radius of a charged particle's path in a magnetic field?
- r = mv/(qB) for motion perpendicular to B. With an angle to B, the path is a helix with pitch 2πm·v·cosθ/(qB).
- How do I find the field at the centre of an arc?
- B = (μ₀I/4πR)·θ, where θ is the angle subtended in radians. A full loop gives μ₀I/2R.
- How is a galvanometer converted into an ammeter or a voltmeter?
- Ammeter: a small shunt resistance in parallel. Voltmeter: a large resistance in series.
- What is the force between two parallel current-carrying wires?
- F/L = μ₀I₁I₂/(2πd). Currents in the same direction attract; opposite currents repel.
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Want this taught live? JEE 2027 & 2028 batches
Moving Charges and Magnetism (Physics) is part of the JEE Main & Advanced syllabus plan. Pick the batch by the year you appear in — Class 11 students join the two-year JEE 2028 program, Class 12 students and repeaters join the one-year or crash program for JEE 2027.
- JEE 2027 online coaching — 1 year Class 12 batchFull syllabus, revision and test series for the JEE Main & Advanced 2027 attempt in batches of 20 — every formula here is drilled through daily practice.
- JEE 2028 two year course for Class 11 studentsStart early: a two-year JEE Main & Advanced 2028 program that builds concepts alongside school, with board-level support.
- JEE 2027 crash course — 90 day intensive revisionFinal-lap program for Class 12 & droppers: complete revision, PYQ marathons and full-length mocks before JEE 2027.
- 1-on-1 JEE 2027 & 2028 tutoring at $15 per hourPersonal mentor, flexible timings and a plan built around the chapters you keep losing marks in.
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