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Electromagnetism

Review your understanding of electromagnetism in this free article aligned to NGSS standards.

Key points:

  • When electric charges move, they create magnetic fields in the space around them.
  • Electric charges moving through a wire create electric current.
  • Because electric currents are made up of moving charges, they create magnetic fields. An electromagnet is a coil of wires that becomes a magnet when electric current runs through it.
    • Electromagnets only work when the electric current is turned on.
    • Increasing the electric current or increasing the number of wire loops increases the strength of the electromagnet.
  • Changing the magnetic field around a coil of wire (by moving a magnet nearby) can create electric current in the wire.
    • Increasing the speed of the moving magnet, using a stronger magnet, or increasing the number of wire loops produces more electric current.
    • Moving the coil of wire around a magnet will also create electric current.

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