The Solenoid

A solenoid consists of an insulated wire twisted around a metallic rod (typically iron). It yields a magnetic field as long as a current runs through the windings. The strength of the magnetic field is proportional to the number of turns of wire. Its advantage over a permanent magnet is that the intensity of the magnetic field can be varied and turned on and off. In the graphic, as electricity is supplied by a battery, the nail and the clip are attracted to the solenoid.

SNAPSHOTS

  • [Snapshot]
  • [Snapshot]
  • [Snapshot]

DETAILS

The strength of the magnetic field at an interior point of a large solenoid is constant, given by , where is the permeability of free space, the number of windings, and the intensity of the electric current.
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.