Which of the following magnetic field (static) lines are correctly represented

Options

A.
B.
C.
D.

Answer

To determine which of the given options correctly represents static magnetic field lines, we can analyze each option based on the fundamental principles of magnetism.

### Step-by-Step Solution:

1. **Understanding Magnetic Field Lines**:
- Magnetic field lines represent the direction and strength of magnetic fields. They have specific characteristics: they emerge from the north pole and enter the south pole, they never intersect, and they form closed loops.

2. **Analyzing Option 1**:
- Option 1 shows a single magnetic pole. This is incorrect because magnetic monopoles do not exist in nature. Every magnet has both a north and a south pole.

**Hint**: Remember that magnetic monopoles have never been observed; every magnet has both poles.

3. **Analyzing Option 2**:
- Option 2 suggests that magnetic field lines intersect. This is also incorrect because no two magnetic field lines can cross each other at a point. If they did, it would imply that the magnetic field has two different directions at that point, which is impossible.

**Hint**: Think about the implications of intersecting lines in terms of direction; it leads to contradictions.

4. **Analyzing Option 3**:
- Option 3 depicts magnetic field lines that do not form closed loops. This is incorrect because magnetic field lines must always form closed loops, either within the magnet or extending into space.

**Hint**: Recall that magnetic field lines must always return to complete a loop.

5. **Analyzing Option 4**:
- Option 4 correctly shows magnetic field lines emerging from a north pole and entering a south pole. This is consistent with the fundamental properties of magnetic fields. Therefore, this option is correct.

**Hint**: Visualize how magnets work; field lines always go from north to south.

### Conclusion:
The correct representation of static magnetic field lines is given in **Option 4**, as it accurately reflects the behavior of magnetic fields by showing lines that emerge from the north pole and terminate at the south pole, without any intersections or isolated poles.