The magnetic field lines around a bar magnet can be traced with the help of

Options

A. iron filings
B. tracing compass
C. both (a) and (b)
D. none of the above.

Explanation

To trace the magnetic field lines around a bar magnet, we can use two methods: iron fillings and a tracing compass. Here’s a step-by-step solution to the question:

### Step-by-Step Solution:

1. **Understanding the Magnetic Field**:
- A bar magnet has two poles: a North pole and a South pole. The magnetic field lines emerge from the North pole and enter the South pole.

2. **Using Iron Fillings**:
- Sprinkle iron fillings evenly around the bar magnet on a piece of paper or a flat surface.
- Gently tap the surface to allow the iron fillings to align themselves according to the magnetic field.

3. **Observation of Iron Fillings**:
- The iron fillings will arrange themselves in a pattern that represents the magnetic field lines.
- The lines will be denser near the poles of the magnet, indicating a stronger magnetic field, and will spread out as they move away from the magnet.

4. **Using a Tracing Compass**:
- Place a small compass at various points around the magnet.
- Observe the direction in which the compass needle points. The needle will align itself along the magnetic field lines.

5. **Recording the Results**:
- By moving the compass around the magnet and marking the direction of the needle at various points, you can trace the magnetic field lines.
- The direction of the needle indicates the direction of the magnetic field at that point.

6. **Conclusion**:
- Both methods (iron fillings and tracing compass) effectively demonstrate the magnetic field lines around a bar magnet.
- Therefore, the answer to the question is that the magnetic field lines around a bar magnet can be traced with the help of both iron fillings and a tracing compass.

### Final Answer:
The magnetic field lines around a bar magnet can be traced with the help of both iron fillings and a tracing compass.

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