Question

The magnetic field around a current-carrying solenoid is similar to the magnetic field of a:

• A. Compass needle
• B. Permanent magnet
• C. Electromagnet
• D. Bar magnet

Hint:

While a solenoid is an electromagnet, the phrasing "similar to the magnetic field of" seeks the classic geometric equivalent, which is universally taught as the bar magnet in electromagnetism.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
The question asks to identify which common magnetic object produces a magnetic field pattern identically shaped to that of a current-carrying solenoid.
Step 2: Detailed Explanation:
A solenoid is a long coil of wire wrapped in many turns. When a direct current passes through it, it produces a magnetic field.
Inside the solenoid, the magnetic field lines are parallel, straight, and densely packed, indicating a strong, uniform magnetic field.
Outside the solenoid, the field lines curve around from one end to the other, emerging from one end (which acts as the North pole) and entering the other end (which acts as the South pole).
This specific spatial distribution of the magnetic field lines is geometrically indistinguishable from the magnetic field produced by a standard cylindrical or rectangular bar magnet.
Step 3: Final Answer:
The magnetic field around a current-carrying solenoid is similar to that of a bar magnet.