Question

a student makes a circuit with a wire wrapped around an iron nail. the wire is connected to a switch and a battery, as shown. when the switch is closed, the iron nail attracts closely placed iron filings. when the switch is open, the iron nail drops the iron filings. which statement best explains the attraction and repulsion of the iron filings? the iron filings are made of the same material as the iron nail. the iron filings have a magnetic field that is strengthened by an energy source. when there is an electric current flowing through the wire, a magnetic field is created around the iron nail. when the wire is wrapped around the iron nail, an electric current is generated that flows when the switch is open.

Explanation:

This is an example of an electromagnet. When an electric current flows through the wire wrapped around the iron nail (when the switch is closed), it creates a magnetic field around the nail, which attracts the iron filings. Without the current (switch open), there is no magnetic field to attract them.

Answer:

When there is an electric current flowing through the wire, a magnetic field is created around the iron nail.