magnet

• What type of force is magnetism?


  Non-contact force
• Which materials are attracted to magnets?

  Iron, nickel, and cobalt
• Why are mixtures like steel attracted to magnets?

  They include a magnetic material
• Which metals are not magnetic?

  Aluminium, copper, and gold
• What is iron oxide used for?

  Making video and music cassettes
• What can magnetic materials do besides being attracted to magnets?

  They can block magnetism
• How can you make a magnet from iron or steel?

  By stroking it with a magnet
• What are the two ends of a bar magnet called?

  North pole and south pole
• What happens when a north pole and a south pole meet?

  They attract each other
• What occurs when two north poles meet?

  They repel each other
• What is the area around a magnet called?

  Magnetic field
• How can you visualize the shape of a magnetic field?

  Using iron filings or a plotting compass
• What do iron filings indicate about a magnet's magnetic field?

  They show where the field is strongest
• What do the field lines of a magnet represent?

  The direction of the magnetic field
• What does a compass do?

  Points north
• How can magnetic materials affect a compass?

  They can change its direction
• How can you create a simple compass?

  Attach a magnetized pin to cork
• What happens when you float a magnetized pin on water?

  It aligns with Earth's magnetic field
• How are magnets used in recycling?

  To sort steel and aluminum cans
• What is an electromagnet?

  A coil of wire with electric current
• How does an electromagnet's magnetic field compare to a bar magnet's?

  It has the same shape
• How can you test the strength of an electromagnet?

  By counting paper clips it picks up
• How can you make an electromagnet stronger?

  • Increase the number of coils of wire
  • Increase the size of the current (voltage)
  • Place an iron core into the coil
• What are some uses of electromagnets?

  Lifting objects, electric bells, and motors
• What happens in a D.C. motor?

  A coil rotates between two magnets
• How does a coil of wire become an electromagnet in a D.C. motor?

  Current running through it forms an electromagnet
• What is the arrangement of the permanent magnets in a D.C. motor?

  Opposite poles facing each other
• What effect does the current have on the coil in a D.C. motor?

  It causes the coil to rotate