Inductor (Coil)

  • Any wire carrying a current is surrounded by a magnetic field; winding the wire into a coil strengthens this field
  • When the current through a coil changes the magnetic field resists the change; this resistance to change is called inductance
  • The unit of inductance is the Henry (H) but as this is a large unit the milli– and micro–Henry (mH, μH) are more commonly used