Magnetic field

Summary

In magnetism and electromagnetism, magnetic field is a physical property of space that quantifies the magnetic influence at a given location. Magnetic fields deflect moving electric charges, apply torques on magnets to twist them in the direction of the magnetic field, and attract or repel magnets and magnetic material such as iron. In addition, a time-varying magnetic field induces electrical currents. Magnetic fields are created by magnetic materials and by moving electric charges. The latter is important in creating electromagnets: devices that precisely control magnetic fields by changing the current through the electromagnet.