Question

We can represent magnetic fields with field lines. the direction of the tangent to a magnetic field line at any point gives the direction of B at that point, and (2) the spacing of the lines represents the magnitude of B - the magnetic field is stronger where the lines are closer together, and conversely. In the middle of a very long solenoid the magnetic field lines are

• A. Circular
• B. perpendicular to axis of solenoid
• C. parallel to the axis of solenoid
• D. None of the three option

Answer 1

Answer: (C)

C

Answer 2

The magnetic field inside a very long solenoid is known to be uniform. This means that the magnetic field lines are straight, parallel to each other, and equally spaced. The direction of these lines is along the axis of the solenoid.

1. Uniformity: In the middle of a very long solenoid, the magnetic field is nearly uniform. This is represented by equally spaced magnetic field lines.
2. Direction: The direction of the magnetic field inside a solenoid is along its axis. Therefore, the magnetic field lines are parallel to the axis of the solenoid.

Based on these properties, the correct description for magnetic field lines in the middle of a very long solenoid is "parallel to the axis of solenoid".