Skin effect: Quiz

Question 1: The ________ J in an infinitely thick plane conductor decreases exponentially with depth d from the surface, as follows:
Maxwell's equationsCurrent densityCapacitanceMagnetic field

Question 2: Silver-plating is most effective at ________ and microwave frequencies, because the very thin skin depth (conduction layer) at those frequencies means that the silver plating can economically be applied at thicknesses greater than the skin depth.
Very high frequencyUltra high frequencyL bandHigh frequency

Question 3: The decline in ________ versus depth is known as the skin effect and the skin depth is a measure of the distance over which the current falls to 1/e of its original value.
Magnetic fieldCurrent densityCapacitanceMaxwell's equations

Question 4: in a ________ or a coil, the ac resistance is also affected by proximity effect, which often causes a much more severe increase in ac resistance.
CableCoaxial cablePower cableCable (disambiguation)

Question 5: Iron rods work well for direct-current (DC) ________ but it is impossible to use them at frequencies much higher than 60 Hz.
Arc weldingGas metal arc weldingWeldingGas tungsten arc welding

Question 6: When an ________ interacts with a conductive material, mobile charges within the material are made to oscillate back and forth with the same frequency as the impinging fields.

Question 7: Skin effect is due to ________ set up by the AC current.
ElectromagnetismElectromotive forceEddy currentMaxwell's equations

Question 8: The skin effect has practical consequences in the design of radio-frequency and ________ circuits and to some extent in AC electrical power transmission and distribution systems.

Question 9: Solid or tubular conductors may also be ________-plated providing a better conductor (the best possible conductor except for superconductors) than copper on the "skin" of the conductor.

Question 10: Litz wire is often used in the windings of high-frequency ________, to increase their efficiency by mitigating both skin effect and, more importantly, proximity effect.
InductorTransformer typesNikola TeslaTransformer