Which of the following is impossible in electromagnetism?

Options

A. Breaking a magnet in half, with one piece having only northpole and the other having only south pole
B. Breaking a charged conductor in half with one piece carrying positive charge and the other carrying negative charge
C. Detecting static electric charges with a compass
D. Detecting steady electric currents with a compass

Answer

To solve the question of which of the following is impossible in electromagnetism, we will analyze each option provided and determine their feasibility based on the principles of electromagnetism.

### Step-by-Step Solution:

1. **Understanding Electromagnetism**:
- Electromagnetism is the branch of physics that studies the interaction between electrically charged particles and the forces they exert on each other. It encompasses electric fields, magnetic fields, and electromagnetic waves.

2. **Analyzing the Options**:
- We need to evaluate each statement to see if it aligns with the principles of electromagnetism.

3. **Option 1**: Breaking a magnet in half results in one piece having only a north pole and the other having only a south pole.
- **Analysis**: This statement is impossible. When a magnet is broken, each piece will always have both a north and a south pole. This is due to the nature of magnetic dipoles; you cannot isolate a single pole.

4. **Option 2**: Breaking a charged conductor in half results in one piece carrying a positive charge and the other carrying a negative charge.
- **Analysis**: This statement is possible. When a charged conductor is divided, the charges can redistribute, leading to one piece having a positive charge and the other having a negative charge.

5. **Option 3**: Detecting static electric charge with a comparator.
- **Analysis**: This statement is possible. Static electric charges can be detected using various methods, including using a comparator or an electroscope.

6. **Option 4**: Detecting steady electric current.
- **Analysis**: This statement is also possible. Steady electric currents can be detected using ammeters or other electrical measuring devices.

7. **Conclusion**:
- After analyzing all the options, we find that **Option 1** is impossible in electromagnetism, as it contradicts the fundamental properties of magnets.

### Final Answer:
**The impossible statement in electromagnetism is: Option 1 - Breaking a magnet in half results in one piece having only a north pole and the other having only a south pole.**

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