Similarly, an electromagnetic coil can transfer energy to another, provided they are in the same orientation and resonate at a matching frequency.

Experts are increasingly interested in the method, which involves placing an electromagnetic coil next to the scalp to alter the pattern of signals in a particular brain area.

But when the scientists used a huge electromagnetic coil to change the orientation of the magnetic field around them, the robins all hopped in the new 'southwest' direction.

The piston inside these dampers contained a single, large electromagnetic coil.

This type of unit uses turns of copper tube wound into an electromagnetic coil.