Question

Which of the following would cause an iron bar to start generating a magnetic field? A Orienting the iron bar so that it points to the North pole.

B Labeling the ends of the bar with "N" and "S".
C Melting the bar completely and letting it cool down slowly.
B Wrapping the bar with a coil of wire that has an electric current.

Answer 1

The correct answer to make an iron bar generate a magnetic field is to wrap it with a coil of wire that has an electric current; this creates an electromagnet.

Step-by-step explanation:

An iron bar can be made into a magnet in several ways, but only one of the options provided will cause the iron bar to start generating a magnetic field. The correct answer is wrapping the bar with a coil of wire through which an electric current is flowing. This creates an electromagnet, where the flow of electricity through the coil generates a magnetic field around the iron core. To understand why, we can turn to Oersted's discovery that an electric current can create a magnetic force around a wire. When a coil of wire is wrapped around an iron bar and current is passed through it, the iron bar becomes magnetized owing to the alignment of magnetic domains within the iron caused by the magnetic field of the current-carrying wire.

Answer 2

Wrapping the bar with a coil of wire that has an electric current.

Step-by-step explanation:

To cause an iron bar to start generating a magnetic field, wrap the bar with a coil that has an electric current.

• This process is known as making magnetics using an electric current.
• There is an interaction between electric and magnetic fields.
• Electrical current can be induced by magnetic fields and magnetism can be induced by electric currents.

Wrapping the bar with a coil of wire that has electric current can cause an iron bar to start producing magnetic fields. This way, the iron bar becomes a magnet.