Grade 12 Physical Sciences · Electricity and Magnetism

Explain the motor effect

Find the direction of the force on a current-carrying wire in a magnetic field, and so which way a motor coil turns.

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Left hand rule Motors Electrodynamics Grade 12 PhysicsMiss Martins Maths and Science
GCSE Physics - Motor Effect - How to Find Force Direction & Strength (2027/28 exams)Cognito
Electrodynamics Motors SUMMARY Grade 12 PhysicsMiss Martins Maths and Science

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Question 1.9 · November 2024 · Paper 1 · National (DBE) · 2 marks

1.9 The diagram below shows a simplified electric motor. The rotation of the coil is observed from the battery.

Which ONE of the following statements is CORRECT while the motor is in operation?

The coil and the ...(2)Diagram for question 1.9
  1. A slip rings rotate anti-clockwise.
  2. B slip rings rotate clockwise.
  3. C commutator rotate clockwise.
  4. D commutator rotate anti-clockwise.

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  1. 3. Question 9.1.4 · November 2023 · Paper 1 · National (DBE) · 2 marks

    9.1 A simplified diagram of a DC electric motor is shown below.

    Answer the questions that follow.Diagram for question 9.1
    9.1.4 State TWO changes that can be made to the motor for the coil to rotate faster.(2)
    Show the memo (2 ticks)
    1. ✓
      First changeAny one of: increase the strength of the magnetic field (e.g. use stronger magnets / bring magnets closer / use curved magnets); increase the current (use a battery with higher potential difference / more cells in series / increase emf); increase the area of the coil; increase the number of turns in the coil.

      1 mark · Explain the motor effect

    2. ✓
      Second changeA different one from the list: stronger magnetic field; larger current; larger coil area; more turns in the coil.

      1 mark · Explain the motor effect

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