While doing an experiment Neeraj fixed a sheet of white paper on a drawing board. He placed a bar magnet in the centre of it. He sprinkled some iron filings uniformly around the bar magnet. Then he tapped the board gently and observed that the iron filings arranged themselves in a particular pattern.
What does the crowding of iron filings at the end of the magnet indicate?

Options

A. Magnetic field is weaker near the poles of the magnet.
B. Magnetic field is strongest near the poles of the magnet.
C. Magnetic field is neither weaker nor strongest near the poles of the magnet.
D. None of these

Answer

To solve the question, we need to analyze the experiment conducted by Neeraj and understand what the crowding of iron filings at the ends of the magnet indicates.

### Step-by-Step Solution:

1. **Understanding the Experiment**: Neeraj placed a bar magnet in the center of a sheet of white paper and sprinkled iron filings around it. When he tapped the board, the iron filings arranged themselves in a specific pattern.

2. **Magnetic Field Lines**: The bar magnet has two poles: a north pole and a south pole. The magnetic field lines emanate from the north pole and enter the south pole. These lines represent the direction and strength of the magnetic field.

3. **Behavior of Iron Filings**: Iron filings are ferromagnetic materials that align themselves along the magnetic field lines when subjected to a magnetic field. This means that the filings will be attracted to areas where the magnetic field is strongest.

4. **Crowding of Iron Filings**: When Neeraj observed that the iron filings crowded at the ends of the magnet, it indicated that the magnetic field is strongest at these points. The density of the magnetic field lines is greater at the poles of the magnet, which corresponds to a stronger magnetic field.

5. **Conclusion**: The crowding of iron filings at the ends of the magnet indicates that the magnetic field is strongest at the poles of the magnet. This is because the magnetic field lines are closer together at the poles, signifying a stronger magnetic force in that region.

### Final Answer:
The crowding of iron filings at the ends of the magnet indicates that the magnetic field is strongest at the poles of the magnet.

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