Extra exam question E5D01
Subelement E5, ELECTRICAL PRINCIPLES· Group E5D
What is the result of conductor skin effect?
- A.Resistance increases as frequency increases because RF current flows closer to the surface (correct answer)
- B.Resistance decreases as frequency increases because electron mobility increases
- C.Resistance increases as temperature increases because of the change in thermal coefficient
- D.Resistance decreases as temperature increases because of the change in thermal coefficient
WhySkin effect causes a conductor's resistance to increase as frequency increases, since RF current flows closer to the surface. Skin effect causes RF current to flow increasingly close to a conductor's surface as frequency rises, shrinking the effective cross-sectional area the current can use and therefore increasing the conductor's effective resistance as frequency goes up, answer A. Resistance doesn't decrease with rising frequency due to electron mobility, and this effect is driven by frequency, not by a temperature-related thermal coefficient the way B and D describe.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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