Permanent and induced magnetism, magnetic forces and fields

• According to the video, what should you be able to do by the end of it?

  Describe forces when magnets are brought together
• What is one thing you should be able to describe by the end of this video?

  The difference between permanent and induced magnets
• What are the two ends of a bar magnet called?

  Poles
• What are the two types of poles on a bar magnet?

  North Pole and South Pole
• Where are the magnetic forces strongest on a magnet?

  At the poles of the magnet
• What happens when two like poles are brought close together?

  They repel each other
• What happens when two unlike poles are brought close together?

  They attract each other
• What type of force is the attraction and repulsion between magnetic poles?

  Non-contact force
• Why is the force between magnets considered a non-contact force?

  Magnets don't have to touch to experience it
• What does a permanent magnet produce?

  Its own magnetic field
• If you bring two permanent magnets together, what determines whether they attract or repel?

  The direction of the poles
• What is an induced magnet?

  An object that becomes a magnet in a magnetic field
• What is a key fact about induced magnetism?

  It always causes a force of attraction
• What happens to induced magnets when the permanent magnet is removed?

  They lose most or all of their magnetism
• Where can you find plenty of questions on permanent and induced magnets?

  In my revision workbook
• According to the video's introduction, what should you be able to describe by the end of the video?

  What's meant by a magnetic field
• What else should you be able to describe by the end of this video?

  How to plot a magnetic field pattern
• What are the two types of magnets mentioned in the video?

  Permanent and induced
• What final skill should you gain from this video?

  Evidence that the Earth's core is magnetic
• What is characteristic of a permanent magnet?

  It always has a magnetic field
• What is an induced magnet?

  A material magnetized when placed in a magnetic field
• Name one of the four magnetic materials mentioned?

  Iron
• How many types of magnetic materials are mentioned as a key fact?

  Four
• What alloy is also a magnetic material?

  Steel
• What is steel an alloy of?

  Iron
• Name one of the other magnetic materials that compose steel alloy?

  Cobalt
• What is the last of the four magnetic materials mentioned?

  Nickel
• What can all four of these magnetic materials be made into?

  A permanent or induced magnet
• What is a magnetic field?

  A region around a magnet with force
• What happens when a magnetic material like iron is placed in a magnetic field?

  It experiences a force of attraction
• What does the strength of the magnetic field depend on?

  Distance from the magnet
• Where is the magnetic field strongest?

  At the poles of the magnet
• What can be used to find the direction of a magnetic field?

  A compass
• What does a magnetic compass contain?

  A small bar magnet
• How do you plot the magnetic field using a compass?

  • Place the compass near the North Pole of the magnet.
  • Draw a cross at the North Pole of the compass.
  • Move the compass so the South Pole is on the cross.
  • Draw a cross at the new North Pole of the compass.
  • Repeat until you plot a complete field line.
  • Connect the dots with a line and add an arrow indicating direction from North to South.
  • Repeat starting at different points around the North Pole.
• What does the proximity of magnetic field lines indicate?

  Where the field is strongest
• What does a compass needle pointing north-south away from magnets suggest?

  Earth has its own magnetic field
• What causes the Earth's magnetic field?

  The Earth's core
• If iron is placed twice as far from a magnet, how does the force change?

  The force of attraction decreases