blog 11: induced voltage and current

A voltage can be induced on a loop or coil of wire if it experiences a changing magnetic field, therefore a changing flux, which causes the loop to have its own magnetic field, therefore its own current.  In other words, if a permanent magnet is moved in and out of a coil of wire, the changing magnetic field from the permanent magnet will induced a voltage and therefore a current in the coil of wire.  Inducing current this way can be an extremely useful way of creating energy and electricity, when an outlet or batteries are not available.  In many flashlights today, you are able to either shake them or turn a crank on them, which in result produces a light.  These flashlights are utilizing induced current from a permanent magnet that moves in and out of a coil of wire when you apply mechanical energy, such as shaking or cranking.  Some of these types of flashlights are also able to store some of the electricity that is produced from the induced current in a capacitor, which is extremely useful in situations where an alternative source of power is not available.