remember

• MAGNETS

  • unlike poles attract
  • magnetic field: region where magnets/magnetic material experience a non-contact force
  • ^ magnetic field is strongest at poles
• permanent magnets: always magnetic and always have poles_ has their own magnetic field
• induced magnet: magnetic materials that turn into a magnet when put into a magnetic field
• COMPASSES show direction of magnetic field

  • move compass around a magnet and trace its position to find what magnetic field looks like

  when NOT near a magnet, they always point NORTH because the EARTH generates its own MAGNETIC FIELD, showing the core must be magnetic
• CURRENT

  • when current flows through a wire, a magnetic field is created around the wire
  • field is made of concentric circles 90° to wire carrying current
  • changing direction of current changes direction of magnetic field
• LARGER current, CLOSER to wire = STRONGER field