Question

If a bar of steel is placed in a solenoid, then it changes to ______.

• A. an electric bell
• B. an electromagnet
• C. a dynamo
• D. a permanent magnet

Answer 1

The correct option is D

a permanent magnet

1. Permanent magnets are materials that retain their magnetic properties after being exposed to a magnetic field.
2. A solenoid is the type of electromagnet which generates a strong magnetic field inside the coil.
3. When a steel bar is placed in a solenoid it becomes a permanent magnet.

Hence, If a bar of steel is placed in a solenoid, then it changes to a permanent magnet.

Therefore, the correct option is option D.