Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
Everyday components like inductors, transformers, and even simple wires rely on the coupling between electric current and magnetic fields. The statement asks whether a current-carrying conductor produces a magnetic field around it, a fundamental concept from Ampere’s law.
Given Data / Assumptions:
Concept / Approach:
Ampere’s circuital law states that the line integral of magnetic field H around a closed path equals current enclosed. For a straight wire, the magnetic field circles the conductor with magnitude proportional to current and inversely proportional to radial distance (B ∝ I / r). The right-hand rule gives the direction of B around the wire when the thumb points with current.
Step-by-Step Solution:
Verification / Alternative check:
Compass deflection near a current-carrying wire demonstrates the presence and direction of the magnetic field; turning current off removes the deflection.
Why Other Options Are Wrong:
Incorrect: contradicts Ampere’s law.
Restrictions to AC or superconductors are unfounded; DC currents also produce magnetic fields, and superconductivity is not required.
Common Pitfalls:
Assuming only coils create fields; even a single straight wire produces a field. Forgetting the 1/r spatial dependence that weakens the field with distance.
Final Answer:
Correct
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