A magnetic field is invisible, but it can be detected using a magnetic compass. A compass contains a small bar magnet on a pivot so that it can rotate. The compass needle points in the direction ...

When an electric current passes through a metal wire, a magnetic field forms around that wire (see diagram at right). Likewise, a wire passing through a magnetic field creates an electric current ...

what a magnetic field looks like. But as the gelatinous orbs in our skull can perceive only a tiny fraction of the EM spectrum, we have to take those textbook diagrams at face value. That is ...

each particle of the emulsion having its own magnetic field, the direction and intensity of which indicates the SIGNAL's AMPLITUDE and FREQUENCY. See diagrams under EMULSION. The most common backings ...

increasing the rate of rotation increasing the strength of the magnetic field increasing the number of turns on the coil The diagram shows four different positions of the coil in an alternator ...