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• Magnetic field


  The region surrounding a magnet in which the force of the magnet can be experienced
• Take a bar magnet and keep it on a table
• Keep a transparent sheet on top of the magnet
• Sprinkling iron filings on the paper

  1. Iron filings will start arranging in a definite pattern around the magnet

  2. This pattern is called a magnetic field

  3. The lines along which the iron filings arrange are called magnetic field lines
• Magnetic field lines


  • They show the direction and strength of the magnetic field
  • They always start from the north pole of the magnet and end at the south pole
  • Inside the magnet, their direction is from the south pole to the north pole
  • They form closed loops
  • They never cross or intersect each other
• Closeness of the magnetic field lines

  • Indicates the strength of the magnetic field in that area
  • More closely packed lines indicate a stronger magnetic field
  • As the lines spread out, the magnetic field weakens
• More iron filings stick at the poles
• Magnetic Field


  The region around a magnetic material or a moving electric charge within which the force of magnetism acts
• Magnetic field lines


  • They are thought to point out of the north pole and then curve around toward the south pole
  • Inside the magnet, the field lines continue on straight toward the north again
  • They are three-dimensional, curving around the magnet in all directions around the length of the bar
• The Earth, like a magnet, also has a north pole and a south pole
• Earth's two kinds of poles

  • Magnetic poles
  • Geographic poles
• Geographic north pole


  True north, all the lines of longitude intersect, the latitude is 90° and is somewhere in the Arctic ocean
• Geographic south pole


  True south, directly opposite on the other side of the planet, somewhere in Antarctica
• Magnetic poles


  A magnet has two opposite poles, the region at each end of a magnet where the external magnetic field is strongest
• Magnetic field lines are continuous loops