Assertion: We cannot think of magnetic field configuration with three poles.
Reason: A bar magnet does exert a torque on itself due to its own field.

Options

A. (a) If both the assertion and reason are true and reason is correct explanation of the assertion .
B. (b) If both the assertion and reason are true but reason is not a correct explanation of the assertion .
C. (c) If the assertion is true but the reason is false.
D. (d) If both assertion and reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that "We cannot think of magnetic field configuration with three poles."

- A bar magnet has two poles: a north pole and a south pole.
- When a magnet is cut, each piece will still have a north and a south pole.
- It is impossible to create a magnetic monopole (a single pole) or a three-pole configuration, as magnetic fields are inherently dipolar.

**Conclusion for Assertion**: The assertion is true because magnetic fields are always dipolar; hence, we cannot have a configuration with three poles.

### Step 2: Analyze the Reason
The reason states that "A bar magnet does exert a torque on itself due to its own field."

- A bar magnet generates a magnetic field around itself, but it does not exert a torque on itself.
- Torque is exerted by an external magnetic field on the magnet, not by the magnet's own field acting on itself.

**Conclusion for Reason**: The reason is false because a magnet does not exert a torque on itself due to its own field.

### Step 3: Final Conclusion
- The assertion is true, while the reason is false.
- Therefore, the correct answer to the question is that the assertion is true and the reason is false.

### Final Answer:
Both assertion and reason are not true; the correct option is that the assertion is true and the reason is false.

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