Answer: The magnetic field turns off.
Step-by-step explanation:
An electromagnet is coiled wire carrying current through it. The current carrying loop produces magnetic field. The strength of the magnetic field varies with the amount of current and number of turns in the wire.
The industrial magnetic field has ferromagnetic material like iron placed at the center. This increases the strength of the magnetic field.
When the electric current is switched off, the magnetic field produced due to coil turns off.