Its copper coil of wire in the transponder, when moved through a magnetic field, produces electrical current that energizes it.
(Its copper coil of wire in the transponder; produces; electrical current that energizes it; T:when moved through a magnetic field) (electrical current; energizes; it)
Its copper coil of wire in the transponder electrical current
produces energizes
electrical current that energizes it T:when moved through a magnetic field
it