A: A bar magnet does not exert a torque on itself due to its own field.
R: One element of a current-carrying non-straight wire exert a force on another element of the same wire.

Options

A. If both Assertion & Reason are the true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reson is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the given question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states: "A bar magnet does not exert a torque on itself due to its own field."

- A bar magnet creates a magnetic field around itself, with field lines emanating from the North pole and terminating at the South pole.
- The torque on a magnetic dipole in a magnetic field is given by the formula \( \tau = \vec{m} \times \vec{B} \), where \( \tau \) is the torque, \( \vec{m} \) is the magnetic moment, and \( \vec{B} \) is the magnetic field.
- However, since the magnetic field produced by the bar magnet itself does not exert a torque on itself, the assertion is correct.

### Step 2: Analyze the Reason (R)
The reason states: "One element of a current-carrying non-straight wire exerts a force on another element of the same wire."

- In a current-carrying wire, each segment of the wire generates a magnetic field around it.
- When you have a non-straight wire, the current flowing through one segment will exert a magnetic force on another segment of the wire due to the interaction of their magnetic fields.
- This means that each element of the wire does indeed exert a force on another element, making the reason also correct.

### Step 3: Determine the Relationship Between A and R
- While both the assertion and reason are correct, the reason does not provide a correct explanation for the assertion. The assertion is about the bar magnet not exerting torque on itself, while the reason discusses forces between elements of a current-carrying wire, which is a different context.

### Conclusion
Since both the assertion and reason are correct, but the reason does not explain the assertion, the answer to the question is that both statements are correct, but the reason is not a correct explanation for the assertion.

### Final Answer
Both A and R are correct, but R is not a correct explanation of A.

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