select the correct answer. an electromagnet i...
select the correct answer. an electromagnet is a device in which moving electric charges (current) in a coil of wire create a magnet. whats one advantage of using electromagnets in devices? a. electromagnets have a strong, constant magnetic field. b. electromagnets are more powerful than permanent magnets. c. electromagnets dont need a source of electricity to work. d. electromagnets can easily be turned on and off.
Answer
# Brief Explanations:
Electromagnets are magnets where the magnetic field is produced by an electric current. Their key advantage is the ability to control the magnetic - field presence by turning the current on or off. Permanent magnets have a constant magnetic field and don't require electricity to maintain their magnetism. The strength of an electromagnet can vary and isn't always stronger than permanent magnets.
# Answer:
D. Electromagnets can easily be turned on and off.