This image and the corresponding animation depict the magnetic field of a current-carrying coil suspended by a spring above a permanent magnet. Depending on the direction of current flow in the wire (that is, on the direction in which the batteries are connected), the coil will either be repelled upwards away from the magnet, or attracted downwards towards it. The animation shows both these cases. The animation illustrates the fact that magnetic pressure supports the coil from below when it is levitated, and magnetic tension pulls the coil downwards towards the magnet when the current is reversed. This visualization corresponds to a real experiment done in 8.02, Introductory Electromagnetism, at MIT.