Skin Effect Question & Answers September 2, 2022 By WatElectronics This article lists 50 Skin Effect MCQs for engineering students. All the Skin Effect Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up on the fundamentals of Skin Effect. The skin effect explains electromagnetic wave energy that is lying on the skin of any conducting material. The nature of materials, diameter & shape of the conductor, length of the conductor, and frequency are the factors affecting skin effect. The process of altering the quantity of electric current for distributing the charge on the conducting substance that results in maintaining the maximum current density near to the conductor’s surface and minimizes exponentially is the skin effect. Skin effect deals with AC type of current and it is raised due to unequal quantity of distribution of current across a conducting element. The factors affected by the skin effects are the conductor's shape, material, and conductor's diameter. When the frequency of skin effect increases, the AC current results in a minimum quantity of skin depth. Due to eddy current reason, skin effect is induced. Maximum skin effect increases the resistance value. Litz wire substance minimizes the high AC resistance occurred due to the skin effect. 1). Skin effect deals with ___ type of current? AC DC Both a and b None of the above None Hint 2). Skin effect is arised due to _____ quantity of distribution of current across a conducting element? Unequal Equal Even Both b and c None Hint 3). Which of the following factors are affected in skin effect? Conductors shape Material Conductors diameter All the above None Hint 4). In skin effect, the current flows between ___ layers of the of the conductor? Outer surface A certain level Lower surface Both b and c None Hint 5). On which of the following parameter does skin depth depends on? Frequency Time period Wavelength All the above None Hint 6). When frequency in skin effect is increased, the AC current results in ___ quantity of skin depth? Maximum Minimum Zero None of the above None Hint 7). The resistance value for maximum skin effect is ? Maximum Minimum Zero Both a and c None Hint 8). Due to which of the following reason skin effect is induced? Eddy current Resistive loss Flux loss Both a and b None Hint 9). Which of the following is the value of skin depth in a copper material at 60Hz? 8.5mm 9mm 10mm 7mm None Hint 10). Frequency is expressed in terms of ____? Hertz Meters Centimeters Joules None Hint 11). Which of the following substance minimises the high AC resistance occurred due to skin effect___? Litz wire Flux wire Aluminum wire All the above None Hint 12). At which frequencies does Litz wire carry AC? Visible light Radio UV All the above None Hint 13). RF frequency defines the vibrational rate of wave of alternating electric ______properties? Current Voltage Resistance Both a and b None Hint 14). Which of the following fields are involved in RF fields? Electric Magnetic Electromagnetic All the above None Hint 15). Which of the following effects are reduced using Litz wire? Skin effect Proximity effect Light effect Both a and b None Hint 16). Which of the following type of current is induced for skin effect with long distance propagation? AC DC Zero Both a and b None Hint 17). Which of the following charge carriers does the current carries? Holes Electrons Neutrons Protons None Hint 18). ____ is the formula of skin depth? J=Js e^[(-(1+j)d/ del)] J=Js e^[((1+j)d/ del)] J=Js *[(-(1+j)d/ del)] J= e^[(-(1+j)d/ del)] None Hint 19). Which of the following is the formula of skin depth with zero magnetic loss? del= Sqrt[2p/wu] *sqrt[sqrt[1+(pwe)^2]+pwe del= Sqrt[2p/wu] / sqrt[sqrt[1+(pwe)^2]+pwe del= Sqrt[2p/wu] *sqrt[sqrt[1+(pwe)^2]-pwe del= Sqrt[2p/wu] *sqrt[sqrt[1+(pwe)^2]*pwe None Hint 20). Which of the following is the formula of angular frequency? 2pif pif 2pi f/2pi None Hint Skin Effect MCQs for Quiz 21). Which of the following is the formula of conductors permeability? u0 ur er e0 to tr vo vr None Hint 22). Which of the following is the formula for conductors permittivity? u0 ur er e0 to tr vo vr None Hint 23). ____ is the function that defines current density when a maximum skin depth with respect to conductor is observed? Bessel function Hilbert’s function Lortz function Lenses function None Hint 24). The flow of current by Skin effect to a minimum conducting area is ___ ? Allows Blocks Restricts Both b and c None Hint 25). _____ type of heating is localized at the bottom of the conducting substance in skin effect? Induction Conduction Resistance Both a and b None Hint 26). Which of the following are the conductor materials used in skin effect? Ferromagnetic materials Better conductors Paramagnetic materials Both a and b None Hint 27). Increase in area of conductor ___ skin effect? Increases Decreases Zero Constant None Hint 28). The skin effect _____ with increase in frequency? Increases Decreases Zero Constant None Hint 29). The skin effect for strand type conductor is_____ as compared to solid conductor? Maximum Minimum Zero Constant None Hint 30). When the frequency of DC type current is null then the skin effect is _____? Zero Infinity 1 Constant None Hint Skin Effect MCQs for Exams 31). Which of the following is the value of skin depth, when the frequency is 100khz? 0.2mm 0.3mm 0.4mm 0.5mm None Hint 32). Which of the following is the formula for skin depth in terms of frequency? f 1/sq(f) f^2 sq(f) None Hint 33). At which frequency skin effect is negligible? 50Hz 100Hz 150Hz 200Hz None Hint 34). Which of the following factors assist in minimizing the skin effect? Minimizing the conductors size Maximizing the voltage Implementing cables All the above None Hint 35). Current is expressed in terms of ____? Amperes Volts Hertz Centimetres None Hint 36). Power transmission are classified in to __ types? AC DC Zero Both a and b None Hint 37). Which of the following is the advantage of DC transmission systems? 2 conductors are required Minimum insulation cost Eliminates phase displacements All the above None Hint 38). Which of the following is the insulators potential stress percentage of DC transmission system as compared with AC transmission system? 70 50 40 30 None Hint 39). Which of the following problems are eliminated by DC transmission type systems? Inductance Capacitance Phase displacements All the above None Hint 40). Electrical energy is transmitted via ___ phase AC transmission? 2 1 3 Multi None Hint Skin Effect MCQs for Interviews 41). Which of the following are the advantages of AC transmission type system? Can be stepped up and down AC substation is maintained at lower cost Power transformation is easy All the above None Hint 42). AC transmission type systems are affected with ____ type of discharge? Flux Corona Magnetic Both a and c None Hint 43). On which of the following substance does resistance law depends on? Substance length Substance area Substance temperature All the above None Hint 44). Resistance is measured in terms of _____? Ohms Amperes Volts Watts None Hint 45). Which of the following is the skin depth of Aluminium? 0.820 0.652 0.753 0.634 None Hint 46). Which of the following is the skin depth of Copper? 0.820 0.652 0.753 0.634 None Hint 47). Which of the following is the skin depth of gold? 0.820 0.652 0.753 0.634 None Hint 48). Which of the following is the skin depth of silver? 0.820 0.652 0.753 0.634 None Hint 49). At which frequency the skin depth is 9220? 50Hz 60Hz 10 kHz 1GHz None Hint 50). At which frequency the skin depth is 2.10? 50Hz 60Hz 10 kHz 1GHz None Hint Please fill in the comment box below. Time's up
