The magnetic field induces currents in metal objects near the search head, and the currents build up a magnetic field in the metal objects.
(The magnetic field; induces; currents; L:in metal objects near the search head) (the currents; build up; a magnetic field in the metal objects)
The magnetic field the currents
induces build up
currents L:in metal objects near the search head
a magnetic field in the metal objects