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Combined Science: Physics

GCSE · Edexcel · foundation

QuestionsFlashcards

Expressing Quantities & SI Units
- Units & Prefixes
  8
- Conversions & Standard Form
  6

Atomic Structure
Radioactive Decay
Dangers of Radiation
- Dangers of Radiation
  5
- Contamination & Irradiation
  6

Magnetism
Electromagnetism & The Motor Effect
- Magnetic Fields in Wires
  6
- Magnetic Fields in Solenoids
  6

Transformers & the National Grid
- The National Grid
  5
- The Ideal Transformer Equation
  3

Permanent & Induced Magnets Flashcards

All 6 cards in this deck

What is an induced magnet?: A material that becomes a magnet when placed in a magnetic field, and loses its magnetism when the magnet is removed.
True or false? A paper clip picked up by a magnet has become a permanent magnet.: False. It is an induced (temporary) magnet — the magnetism is lost when the magnet is removed.
Which is more suitable for making a temporary magnet (such as an electromagnet core), iron or steel?: Iron (soft iron) — it loses its magnetism easily when the field is removed, whereas steel keeps its magnetism, so steel is better for permanent magnets.
True or false? Showing that a paper clip is attracted to a magnet proves the paper clip has kept some magnetism.: False. Any magnetic material is attracted to a magnet; only repulsion shows the paper clip is itself magnetised.
What is a permanent magnet?: A magnet that makes its own magnetic field at all times, e.g. a bar magnet. It does not need to be in another magnetic field.
Why can a large magnet pick steel cans out of mixed waste but not aluminium cans?: Steel is a magnetic material, so the steel cans become induced magnets and are attracted to the magnet. Aluminium is not magnetic, so those cans are left behind.