O-Level Physics Electricity & Magnetism: The Complete Study Guide
Electricity and Magnetism is one of the most heavily tested topics in O-Level Physics. This complete guide covers every concept, formula, and exam technique you need to score A1.
Electricity and Magnetism consistently appears in every O-Level Physics paper, making it one of the highest-priority topics for revision. Our Physics tutors at Sophia Education have compiled this comprehensive guide covering every concept and formula tested at O-Level.
Key Formulas You Must Know
- ✓V = IR (Ohm's Law)
- ✓P = IV = I²R = V²/R (Power)
- ✓E = Pt (Energy)
- ✓Q = It (Charge)
- ✓For series circuits: R_total = R1 + R2 + R3
- ✓For parallel circuits: 1/R_total = 1/R1 + 1/R2 + 1/R3
Series vs Parallel Circuits — The Key Differences
In a series circuit: current is the same throughout, voltage is shared across components, total resistance is the sum of individual resistances. In a parallel circuit: voltage is the same across all branches, current is shared, total resistance is less than the smallest individual resistance.
Electromagnetic Induction — Fleming's Rules
Use Fleming's Right-Hand Rule for generators (motion → current): thumb = motion, index = field, middle = current. Use Fleming's Left-Hand Rule for motors (current → motion): thumb = force/motion, index = field, middle = current. The key difference: generators convert mechanical energy to electrical energy; motors do the opposite.
Exam Tip: When drawing circuit diagrams, always use a ruler and the correct circuit symbols. A poorly drawn diagram can cost you marks even if your calculations are correct.
Sophia Education's O-Level Physics tutors provide step-by-step guidance on circuit problems and electromagnetic induction. Our small-group classes ensure every student understands every concept before moving on.
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WhatsApp Us Now →📞 +65 8875 0044About the Author
Mr Bryan Chew is a specialist tutor at Sophia Education Singapore, with extensive experience teaching O-Level Physics to students across JC, O-Level, IP, and PSLE levels.
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