Assertion : Electric field outside the conducting wire which carreis a constant is zero.
Reason : Net charge on conducting wire is zero.

Options

A. If both assertion and reason are ture and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If assertion and reason both are false.

Explanation

To solve the question, we need to analyze the assertion and the reason given:

**Assertion**: The electric field outside the conducting wire which carries a constant current is zero.

**Reason**: The net charge on the conducting wire is zero.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- When a conducting wire carries a constant current, it means that there is a steady flow of charge (usually electrons) through the wire.
- In electrostatics, the electric field outside a conductor in electrostatic equilibrium is zero. However, when current flows, the situation is slightly different. The electric field inside the conductor is non-zero to maintain the current, but outside the conductor, the electric field can be considered negligible or zero for an ideal infinite wire.

2. **Understanding the Reason**:
- The reason states that the net charge on the conducting wire is zero. This is true for a neutral conductor. When current flows through the wire, the charges are in motion, but the overall charge remains neutral (zero net charge) as long as no excess charge is added to or removed from the wire.
- The moving charges create a magnetic field around the wire, but they do not create an external electric field.

3. **Connecting Assertion and Reason**:
- The assertion that the electric field outside the conducting wire is zero can be explained by the reason that the net charge on the wire is zero. Since the wire is neutral, it does not create an electric field in the surrounding space.
- Therefore, the assertion is true and the reason is also true, and the reason correctly explains the assertion.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason is a correct explanation of the assertion. Thus, the answer to the question is that both the assertion and reason are true.

### Final Answer:
Both the assertion and reason are true, and the reason correctly explains the assertion.

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