When an iron nail wrapped in a copper wire is attached to a circuit, it forms
A B C D
a battery. an engine. an insulator. an electromagnet.
Question: When an iron nail wrapped in a copper wire is attached to a circuit, it forms
(A) a battery.
(B) an engine.
(C) an insulator.
(D) an electromagnet.

Answer: (D) an electromagnet.
Answer: (A) a battery.
Question: When an iron nail wrapped in a copper wire is attached to a circuit, it forms
(A) a battery.
(B) an engine.
(C) an insulator.
(D) an electromagnet.
Answer: (D) an electromagnet.