MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Magnetic field round an electric wire. Iron filings (grey) being used to show the circular magnetic field associated with an electrical wire. The wire (brown) is running vertically down towards the paper on which the filings have been scattered. Magnetism is caused by the regular alignment of electrons within materials like metals, which explains why a regular flow of electrons (an electric current) produces the same phenomenon.
Model release not required. Property release not required.