Magnets

• How do we represent magnetic fields?

  Using field lines
• What is a magnet?

  Any material that produces a magnetic field
• What is the most common type of magnet?

  Bar magnets
• What do all magnets have in common?

  They have a north and a south pole
• What do magnetic field lines represent?

  The direction and strength of the magnetic field
• How do you draw magnetic field lines?

  From the north pole to the south pole
• What is the easiest way to draw field lines?

  One straight line into south, out of north
• What do denser field lines indicate?

  A stronger magnetic field
• How can we find the poles of a magnet?

  Using a compass
• Why does a compass needle point towards a magnet's south pole?

  Because it is a tiny bar magnet
• What happens when you push two north poles of magnets together?

  They repel each other
• What occurs when opposite poles of magnets are brought together?

  They attract each other
• What are the steps to represent a magnetic field using field lines?

  • Draw a straight line into the south pole
  • Draw a straight line out of the north pole
  • Add a pair of slightly curved lines into the south pole
  • Add a similar pair coming out of the north pole
  • Draw loops from north to south
  • Ensure arrows point out of north and into south
• How do magnetic fields interact between two magnets?

  • North poles repel each other
  • Opposite poles attract each other
  • Field lines show the interaction force
• What is a magnetic material?

  Any object influenced by a magnetic field
• What distinguishes an actual magnet from a magnetic material?

  An actual magnet produces a magnetic field
• Which elements are commonly known as magnetic materials?

  Nickel, cobalt, and iron
• Why is nickel considered a magnetic material?

  It can be influenced by a magnetic field
• What acronym can help remember common magnetic elements?

  NCIS
• What are permanent magnets?

  Magnets that produce a magnetic field constantly
• What are induced or temporary magnets?

  Magnets that have a magnetic field temporarily
• How is an induced magnet created?

  By placing a magnetic material in a magnetic field
• What happens to an induced magnet when removed from a magnetic field?

  It loses its magnetism
• What are magnetically soft materials?

  Materials that lose magnetism quickly
• What are magnetically hard materials?

  Materials that lose magnetism slowly
• What are the differences between permanent magnets and induced magnets?

  • Permanent magnets:
  • Produce a magnetic field constantly
  • Induced magnets:
  • Have a magnetic field temporarily
  • Created by external magnetic fields
• What is the relationship between permanent and induced magnets?

  • The force between them is always attractive
  • Induced magnets develop their own north and south poles