Plotting Magnetic Fields

• Two types of plotting magnetic fields around a bar magnet:

  • Iron fillings
  • Plotting compasses
• Iron fillings

  1. place a piece of paper on top of the magnet
  2. gently sprinkle fillings on the paper
  3. carefully tape the paper to allow the fillings to settle on the field lines

  
• Plotting compasses

  1. place the magnet on top of a piece of paper
  2. draw a dot at one end of the magnet, near the corner
  3. place plotting compasses next to the dot so that one end of the needle is pointing towards dot
  4. draw a new dot at the other side of the compass needle
  5. move the compass so that it points towards the new dot, repeat the process
  6. once you have a chain of dots, remove the compass and link the dots together by drawing a smooth curve
  7. the direction of the line is the same as the compasses
  8. now repeat this process several times until you gain a complete magnetic field
• How many field lines to draw when plotting magnetic fields?

  At least 3