Description : The phase shift in the electric and magnetic fields in an EM wave is given by which parameter? a) phase constant b) attenuation constant c) propagation constant d) intrinsic impedance
Last Answer : d) intrinsic impedance
Description : In good conductors, the electric and magnetic fields will be a) 45 in phase b) 45 out of phase c) 90 in phase d) 90 out of phase
Last Answer : b) 45 out of phase
Description : In electric fields, D= ε E. The correct expression which is analogous in magnetic fields will be a) H = μ B b) B = μ H c) A = μ B d) H = μ A
Last Answer : b) B = μ H
Description : Choose the best definition of dielectric loss. a) Absorption of electric energy by dielectric in an AC field b) Dissipation of electric energy by dielectric in a static field c) Dissipation of heat by dielectric d) Product of loss tangent and relative permittivity
Last Answer : a) Absorption of electric energy by dielectric in an AC field
Description : The line integral of which parameter is zero for static fields? a) E b) H c) D d) B
Last Answer : a) E
Description : For static fields, the curl of E will be a) Rotational b) Irrotational c) Solenoidal d) Divergent
Last Answer : b) Irrotational
Description : Which of the following identities is always zero for static fields? a) Grad(Curl V) b) Curl(Div V) c) Div(Grad V) d) Curl(Grad V)
Last Answer : d) Curl(Grad V)
Description : It cannot be determined from Gauss law, whereas the remaining options can be computed from Gauss law. 10. Gauss law for magnetic fields is given by a) Div(E) = 0 b) Div(B) = 0 c) Div(H) = 0 d) Div(D) = 0
Last Answer : b) Div(B) = 0
Description : The skin depth is used to find which parameter? a) DC resistance b) AC resistance c) Permittivity d) Potential
Last Answer : b) AC resistance
Description : The curl of the electric field intensity is a) Conservative b) Rotational c) Divergent d) Static
Last Answer : b) Rotational
Description : In conductors, the E and H vary by a phase difference of a) 0 b) 30 c) 45 d) 60
Last Answer : c) 45
Description : The power in a electromagnetic wave with electric field and magnetic field intensities 12 and 8 respectively is a) 96 b) 12 c) 8 d) 48
Last Answer : d) 48
Description : The electric and magnetic field components in the electromagnetic wave propagation are in phase. State True/False. a) True b) False
Last Answer : a) True
Description : Zero permeability/permittivity implies which state? a) No ions are allowed in the medium b) No current is generated in the medium c) No magnetic or electric energy is permitted in the medium d) No resistivity
Last Answer : c) No magnetic or electric energy is permitted in the medium
Description : In perfect conductors, the phase shift between the electric field and magnetic field will be a) 0 b) 30 c) 45 d) 90
Description : In lossy dielectric, the phase difference between the electric field E and the magnetic field H is a) 90 b) 60 c) 45 d) 0
Last Answer : d) 0
Description : The line integral of the electric field intensity is a) Mmf b) Emf c) Electric potential d) Magnetic potential
Last Answer : b) Emf
Description : Which quantity is solenoidal in the electromagnetic theory? a) Electric field intensity b) Electric flux density c) Magnetic field intensit d) Magnetic flux density
Last Answer : d) Magnetic flux density
Description : Find the electric field applied on a system with electrons having a velocity 5m/s subjected to a magnetic flux of 3.6 units. a) 15 b) 18 c) 1.38 d) 0.72
Last Answer : b) 18
Description : Find the Lorentz force of a charge 2.5C having an electric field of 5 units and magnetic field of 7.25 units with a velocity 1.5m/s. a) 39.68 b) 68.39 c) 86.93 d) 93.68
Last Answer : a) 39.68
Description : When the electric field travels in +x direction and the EM wave is travelling the –y direction, then the magnetic field will be travelling in which direction? a) +z direction b) –z direction c) Either +z or –z direction d) Does not trave
Last Answer : c) Either +z or –z direction
Description : The inductance is the measure of a) Electric charges stored by the material b) Emf generated by energising the coil c) Magnetic field stored by the material d) Magnetization of dipoles
Last Answer : c) Magnetic field stored by the material
Description : Find the electric field when the magnetic field is given by 2sin t in air. a) 8π x 10 -7 cos t b) 4π x 10 -7 sin t c) -8π x 10 -7 cos t d) -4π x 10 -7 sin t
Last Answer : a) 8π x 10 -7 cos t
Description : Electric field will be maximum outside the conductor and magnetic field will be maximum inside the conductor. State True/False. a) True b) False
Description : Biot Savart law in magnetic field is analogous to which law in electric field? a) Gauss law b) Faraday law c) Coulomb’s law d) Ampere law
Last Answer : c) Coulomb’s law
Description : The capacitance of a material refers to a) Ability of the material to store magnetic field b) Ability of the material to store electromagnetic field c) Ability of the material to store electric field d) Potential between two charged plates
Last Answer : c) Ability of the material to store electric field
Description : Curie-Weiss law is used to calculate which one of the following? a) Permittivity b) Permeability c) Electric susceptibility d) Magnetic susceptibility
Last Answer : d) Magnetic susceptibility
Description : The superconducting materials will be independent of which of the following? a) Magnetic field b) Electric field c) Magnetization d) Temperature
Last Answer : b) Electric field
Description : Debye is the unit used to measure a) Permittivity b) Electric dipole moment c) Magnetic dipole moment d) Susceptibility
Last Answer : b) Electric dipole moment
Description : In electromagnetic waves, the electric field will be perpendicular to which of the following? a) Magnetic field intensity b) Wave propagation c) Both H and wave direction d) It propagates independently
Last Answer : c) Both H and wave direction
Description : Harmonic electromagnetic fields refer to fields varying sinusoidally with respect to time. State True/False. a) True b) False
Description : Which of the substances listed can be used to shield sensitive equipment from static magnetic fields? A. Glass B. Mica C. Bakelite D. Permeable iron
Last Answer : Answer: D
Description : The most practical way to control the voltage output of an AC generator is to vary the _____________. A. number of windings B. speed of the rotating field C. strength of the rotating magnetic field D. power factor of the load
Last Answer : Answer: C
Description : For time varying currents, the field or waves will be a) Electrostatic b) Magneto static c) Electromagnetic d) Electrical
Last Answer : c) Electromagnetic
Description : Regarding an AC generator connected to the main electrical bus; as the electric load and power factor vary, a corresponding change is reflected in the generator armature reaction. These changes in ... . governor speed droop setting B. voltage regulator C. balance coil D. phase-balance relay
Last Answer : Answer: B
Description : Find the force experienced by an electromagnetic wave in a conductor? a) Electrostatic force b) Magneto static force c) Electro motive force d) Lorentz force
Last Answer : d) Lorentz force
Description : In which of the following forms can Maxwell’s equation not be represented? a) Static b) Differential c) Integral d) Harmonic
Last Answer : a) Static
Description : A field in which a test charge around any closed surface in static path is zero is called a) Solenoidal b) Rotational c) Irrotational d) Conservativ
Last Answer : d) Conservative
Description : One method of testing for a reversed shunt field coil in a DC generator or motor is by connecting the field to a direct current source, at reduced field rated voltage, and test for ... placed near each field C. test lamp across adjacent fields D. copper jumper across the interpole connections
Description : The relative speed between the magnetic fields of stator and rotor under steady state operation is zero for a (A) dc machine. (B) 3 phase induction machine. (C) synchronous machine. (D) single phase induction machine.
Last Answer : Ans: all options are correct
Description : On some diesel-electric ships, the DC propulsion motor will only attain half speed when the generator fields are fully excited. Speeds above this are obtained by _____________. A. rotating brush ... B. raising the generator engine speed C. lowering the generator engine speed D. decreasing excitation
Description : At dc field, the displacement current density will be a) 0 b) 1 c) Jc d) ∞
Last Answer : a) 0
Description : Calculate the loss tangent when the dielectric constant in AC field is given by 3 + 2j. a) (2/3) b) (3/2) c) (-3/2) d) (-2/3)
Last Answer : d) (-2/3)
Description : The voltage at any point in an ac circuit will be a) Peak voltage b) RMS voltage c) Average voltage d) Source voltage
Last Answer : b) RMS voltage
Description : What are the OBSERVED differences between electric and magnetic fields?
Last Answer : answer:A changing magnetic field creates an electric current (a flow of electrically charged material). A changing electric current, in turn, creates a magnetic field.
Description : In a cathode ray tube, electric and magnesity of the magnetic fields are simultaneously applied at right angles to each other and the intensity of the
Last Answer : In a cathode ray tube, electric and magnesity of the magnetic fields are simultaneously applied at right angles to each ... 01 T` and `E=50,000 V//m`.
Description : The forces of cathode ray particles due to electric and magnetic fields which are at right angles to each other balance each other. If the magnetic fi
Last Answer : The forces of cathode ray particles due to electric and magnetic fields which are at right angles to ... p.d. is required to produce this velocity?
Description : A charged particle with a velocity `2xx10^(3) ms^(-1)` passes undeflected through electric field and magnetic fields in mutually perpendicular directi
Last Answer : A charged particle with a velocity `2xx10^(3) ms^(-1)` passes undeflected through electric field and magnetic fields ... 1)` D. `1.33xx10^(3)NC^(-1)`
Description : What kinds of waves are produced by disturbances in electric and magnetic fields?
Last Answer : Feel Free to Answer
Description : What is meant by referring to electromagnetic waves as horizontally polarized? A. The electric field is parallel to the earth. B. The magnetic field is parallel to the earth. C. Both the electric and magnetic fields are horizontal D. Both the electric and magnetic fields are vertical
Last Answer : A. The electric field is parallel to the earth.