This exam focus covers Exam Focus within The Motor Effect for GCSE Physics. Revise The Motor Effect in Magnetism for GCSE Physics with 19 exam-style questions and 12 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 10 of 12 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
🎯 Exam Focus
Frequently Examined
Motor effect questions appear regularly, especially at higher tier. Examined in Edexcel 1PH0/2 (Paper 2). Edexcel frames questions around real applications — loudspeaker coils, electric motors in appliances, railgun-style devices — so practise applying F = BIL to context you haven't seen before. Edexcel higher tier also uses "magnetic flux density" (B) explicitly in questions and mark schemes.
- Fleming's Left-Hand Rule (2 marks): Given two of the three directions (current, field, force), find the third. Practice using the actual hand rule.
- F = BIL calculation (3 marks): Straightforward substitution. Show working, give units (N).
- DC motor explanation (3-4 marks): Explain the role of the commutator — reverses current every half turn to maintain continuous rotation.
- How to increase motor speed (2 marks): More current, stronger magnets, more turns. Explaining each earns marks.
- "What happens if current reverses?" (2 marks): Force reverses direction — motor spins in opposite direction.
- "Suggest" questions (Edexcel): Given an unfamiliar coil configuration or novel device, suggest how the force could be increased or its direction changed — apply the three B, I, L factors.
Practice questions for The Motor Effect
What is the motor effect?
Explain how Fleming's left-hand rule is used to find the direction of the force on a current-carrying conductor in a magnetic field.