The change in the cross-sectional area of a conductor in a magnetic field will affect both the reluctance and the resistance of the conductor. Therefore, the correct answer is C: “(A) and (B) both in the same way.”
Here’s a further explanation:
A. Reluctance of conductor: Reluctance is a property that opposes the flow of magnetic flux through a material. It is analogous to resistance in electrical circuits. The reluctance of a conductor depends on its dimensions, including the cross-sectional area. When the cross-sectional area of the conductor changes, the reluctance also changes. An increase in cross-sectional area decreases the reluctance, allowing more magnetic flux to flow through the conductor.
B. Resistance of conductor: Resistance is a property that opposes the flow of electrical current through a material. The resistance of a conductor is primarily determined by its dimensions, including the cross-sectional area. When the cross-sectional area of the conductor changes, the resistance also changes. According to the formula for resistance (R = ρ * (L / A)), where ρ is the resistivity of the material, L is the length of the conductor, and A is the cross-sectional area, an increase in cross-sectional area (A) decreases the resistance (R) of the conductor.
Therefore, both the reluctance and resistance of the conductor are affected in the same way by a change in the cross-sectional area of the conductor in a magnetic field.