Description : The loss tangent is also referred to as a) Attenuation b) Propagation c) Dissipation factor d) Polarization
Last Answer : c) Dissipation factor
Description : Find the loss tangent of a material with conduction current density of 5 units and displacement current density of 10 units. a) 2 b) 0.5 c) 5 d) 10
Last Answer : b) 0.5
Description : The loss tangent refers to the a) Power due to propagation in conductor to that in dielectric b) Power loss c) Current loss d) Charge loss
Last Answer : a) Power due to propagation in conductor to that in dielectric
Description : At high frequencies, which parameter is significant? a) Conduction current b) Displacement current c) Attenuation constant d) Phase constant
Last Answer : b) Displacement current
Description : Both the conduction and displacement current densities coexist in which medium? a) Only conductors in air b) Only dielectrics in air c) Conductors placed in any dielectric medium d) Both the densities can never coexist
Last Answer : c) Conductors placed in any dielectric medium
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 charge build up in a capacitor is due to a) Conduction current density b) Displacement current density c) Polarisation d) Magnetization
Last Answer : b) Displacement current density
Description : When the conduction current density and displacement current density are same, the dissipation factor will be a) Zero b) Minimum c) Maximum d) Unity
Last Answer : d) Unity
Description : The loss tangent of a perfect dielectric will be a) Zero b) Unity c) Maximum d) Minimum
Last Answer : d) Minimum
Description : Compute the loss factor when the loss tangent is 0.88 and the real part of dielectric is 24. a) 12.12 b) 12.21 c) 21.21 d) 21.12
Last Answer : d) 21.12
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 : If the loss tangent is very less, then the material will be a a) Conductor b) Lossless dielectric c) Lossy dielectric d) Insulator
Last Answer : b) Lossless dielectric
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 : The attenuation in a good dielectric will be non- zero. State True/False. a) True b) False
Last Answer : a) True
Description : For a lossless dielectric, the attenuation will be a) 1 b) 0 c) -1 d) Infinity
Last Answer : b) 0
Description : The charge build up in the capacitor is due to which quantity? a) Conduction current b) Displacement current c) Convection current d) Direct current
Last Answer : d) Direct current
Description : The current in a metal at any frequency is due to a) Conduction current b) Displacement current c) Both conduction and displacement current d) Neither conduction nor displacement current
Last Answer : a) Conduction current
Description : In pure dielectrics, the parameter that is zero is a) Attenuation b) Propagation c) Conductivity d) Resistivity
Last Answer : c) Conductivity
Description : In free space, the condition that holds good is a) Minimum attenuation and propagation b) Minimum attenuation and maximum propagation c) Maximum attenuation and minimum propagation d) Maximum attenuation and propagation
Last Answer : b) Minimum attenuation and maximum propagation
Description : An example for lossless propagation is a) Dielectric waveguide propagation b) Conductor propagation c) Cavity resonator propagation d) It is not possible
Last Answer : d) It is not possible
Description : Calculate the frequency at which the conduction and displacement currents become equal with unity conductivity in a material of permittivity 2. a) 18 GHz b) 9 GHz c) 36 GHz d) 24 GHz
Last Answer : b) 9 GHz
Description : Referred to the dielectric constant of a transmission line material. A. Inductance and capacitance B. Velocity factor C. Characteristic impedance D. Propagation velocity
Last Answer : B. Velocity factor
Description : Polarizability is defined as the a) Product of dipole moment and electric field b) Ratio of dipole moment to electric field c) Ratio of electric field to dipole moment d) Product of dielectric constant and dipole moment
Last Answer : b) Ratio of dipole moment to electric field
Description : Compute the conductivity when the current density is 12 units and the electric field is 20 units. Also identify the nature of the material. a) 1.67, dielectric b) 1.67, conductor c) 0.6, dielectric d) 0.6, conductor
Last Answer : c) 0.6, dielectric
Description : At dc field, the displacement current density will be a) 0 b) 1 c) Jc d) ∞
Last Answer : a) 0
Description : Find the equation of displacement current density in frequency domain. a) Jd = jwεE b) Jd = jwεH c) Jd = wεE/j d) Jd = jεE/w
Last Answer : a) Jd = jwεE
Description : Find the displacement current density of a material with flux density of 5sin t a) 2.5cos t b) 2.5sin t c) 5cos t d) 5sin t
Last Answer : c) 5cos t
Description : Find the displacement current when the flux density is given by t 3 at 2 seconds. a) 3 b) 6 c) 12 d) 27
Last Answer : c) 12
Description : Find the magnitude of the displacement current density in air at a frequency of 18GHz in frequency domain. Take electric field E as 4 units. a) 18 b) 72 c) 36 d) 4
Last Answer : d) 4
Description : Calculate the displacement current density when the electric flux density is 20sin 0.5t. a) 10sin 0.5t b) 10cos 0.5t c) 20sin 2t d) 20cos 2t
Last Answer : b) 10cos 0.5t
Description : Calculate the conduction current density when the resistivity of a material with an electric field of 5 units is 4.5 units. a) 22.5 b) 4.5/5 c) 5/4.5 d) 9.5
Last Answer : c) 5/4.5
Description : The magnitude of the conduction current density for a magnetic field intensity of a vector yi + zj + xk will be a) 1.414 b) 1.732 c) -1.414 d) -1.732
Last Answer : b) 1.732
Description : Find the conduction current density of a material with conductivity 200units and electric field 1.5 units. a) 150 b) 30 c) 400/3 d) 300
Last Answer : d) 300
Description : Calculate the electric field when the conductivity is 20 units, electron density is 2.4 units and the velocity is 10m/s. Assume the conduction and convection current densities are same. a) 2.4 b) 4.8 c) 3.6 d) 1.2
Last Answer : d) 1.2
Description : Find the conductivity of a material with conduction current density 100 units and electric field of 4 units. a) 25 b) 400 c) 0.04 d) 1600
Last Answer : a) 25
Description : Find the conduction current density when conductivity of a material is 500 units and corresponding electric field is 2 units. a) 500 b) 250 c) 1000 d) 2000
Last Answer : c) 1000
Description : Electric flux density in electric field is referred to as a) Number of flux lines b) Ratio of flux lines crossing a surface and the surface area c) Direction of flux at a point d) Flux lines per unit area
Last Answer : b) Ratio of flux lines crossing a surface and the surface area
Description : The attenuation constant is 0.5 units. The skin depth will be a) 0.5 b) 0.25 c) 2 d) 4
Last Answer : c) 2
Description : The skin depth of a conductor with attenuation constant of 7 neper/m is a) 14 b) 49 c) 7 d) 1/7
Last Answer : d) 1/7
Description : Calculate the attenuation constant of a conductor of conductivity 200 units, frequency 1M radian/s in air. a) 11.2 b) 1.12 c) 56.23 d) 5.62
Last Answer : a) 11.2
Description : Calculate the phase constant of a conductor with attenuation constant given by 0.04 units. a) 0.02 b) 0.08 c) 0.0016 d) 0.04
Last Answer : d) 0.04
Description : The attenuation constant in lossless dielectrics will be a) 0 b) 1 c) -1 d) ∞
Description : In conductors, which two parameters are same? a) Wavelength and phase constant b) Phase and attenuation constant c) Attenuation constant and skin depth d) Skin depth and wavelength
Last Answer : b) Phase and attenuation constant
Description : Calculate the skin depth of a material with attenuation constant of 2 units. a) 2 b) 1 c) 0.5 d) 4
Last Answer : c) 0.5
Description : For conductors, the loss tangent will be a) Zero b) Unity c) Maximum d) Minimum
Last Answer : c) Maximum
Description : The complex permittivity is given by 2-j. Find the loss tangent. a) 1/2 b) -1/2 c) 2 d) -2
Last Answer : a) 1/2
Description : Find the loss angle in degrees when the loss tangent is 1. a) 0 b) 30 c) 45 d) 90
Last Answer : c) 45
Description : The expression for the loss tangent is given by a) σ/ωε b) ωε/σ c) σ/ω d) ω/ε
Last Answer : a) σ/ωε
Description : If the intrinsic angle is 20, then find the loss tangent. a) tan 20 b) tan 40 c) tan 60 d) tan 80
Last Answer : b) tan 40
Description : Calculate the phase constant of a dielectric with frequency 6 x 10 6 in air. a) 2 b) 0.2 c) 0.02 d) 0.002
Last Answer : c) 0.02