The Motor Effect

Part of The Motor Effect · Section 2 of 12

Deep DiveUnit: MagnetismGCSE

This deep dive covers The Motor Effect 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 2 of 12 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

🔬 The Motor Effect

When a current-carrying conductor is placed in a magnetic field, it experiences a force. This happens because the conductor's own magnetic field (from the current) interacts with the external field.

The principle: A current-carrying conductor in a magnetic field experiences a force.

F = B × I × L
Force (N) = magnetic flux density (T) × current (A) × length in field (m)

Conditions:

  • Current must be flowing through the conductor
  • Conductor must be in a magnetic field
  • Current must NOT be parallel to field (maximum force when perpendicular)

To increase the force:

  • Increase the magnetic field strength (stronger magnets, larger B)
  • Increase the current (larger I)
  • Increase the length of wire in the field (larger L)

Practice questions for The Motor Effect

What is the motor effect?

  • A. A force experienced by a current-carrying conductor placed in a magnetic field
  • B. The generation of a voltage when a conductor moves through a magnetic field
  • C. The heating of a wire when a large current flows through it
  • D. The attraction between two permanent magnets
1 markfoundation

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.

2 marksstandard

Quick recall flashcards

Fleming's Left Hand: for?
Motors (force on current-carrying conductor)
Left hand: thumb =?
Motion/Force

19 questions on The Motor Effect — practise free

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