Description : The ratio of conduction to displacement current density is referred to as a) Attenuation constant b) Propagation constant c) Loss tangent d) Dielectric constant
Last Answer : c) Loss tangent
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 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 : In pure dielectrics, the parameter that is zero is a) Attenuation b) Propagation c) Conductivity d) Resistivity
Last Answer : c) Conductivity
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 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 : 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 : 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 : Find the dissipation factor when series resistance is 5 ohm and capacitive resistance is 10 unit. a) 2 b) 0.5 c) 1 d) 0
Last Answer : b) 0.5
Description : The loss tangent of a perfect dielectric will be a) Zero b) Unity c) Maximum d) Minimum
Last Answer : d) Minimum
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 : 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
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 : 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 : 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 : ECE Board Exam November 1996 The loss in signal power as light travels down a fiber is A. attenuation B. propagation C. absorption D. scattering
Last Answer : A. attenuation
Description : The loss in signal power as light travels down the fiber is called ............. A) Attenuation B) Propagation C) Scattering D) Interruption
Last Answer : A) Attenuation
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 attenuation in a good dielectric will be non- zero. State True/False. a) True b) False
Last Answer : a) True
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) ∞
Last Answer : a) 0
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 a lossless dielectric, the attenuation will be a) 1 b) 0 c) -1 d) Infinity
Last Answer : b) 0
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 : The energy in a magnetic material is due to which process? a) Emf b) Magnetization c) Magnetostriction d) Polarization
Last Answer : b) Magnetization
Description : The mathematical perception of the gradient is said to be a) Tangent b) Chord c) Slope d) Arc
Last Answer : c) Slope
Description : The cylindrical coordinate system is also referred to as a) Cartesian system b) Circular system c) Spherical system d) Space system
Last Answer : b) Circular system
Description : In digital ICs, Schottky transistors are preferred over normal transistors because of their (A) Lower Propagation delay. (B) Higher Propagation delay. (C) Lower Power dissipation. (D) Higher Power dissipation.
Last Answer : Ans: A Lower propagation delay as shottky transistors reduce the storage time delay by preventing the transistor from going deep into saturation.
Description : Define following terms related to logic families : (i) Noise Margin (ii) FAN-OUT (iii) Propagation delay (iv) Power dissipation
Last Answer : i) Noise immunity is measured in terms of noise margin. High state Noise margin = VNH = VOH(min) - VIH(min) Low state Noise margin = VNL = VIL(max) - VOL(max) i) The fan-out is defined as the ... logical 0 state (HIGH to LOW) iii) Average power dissipation is defined as PD(avg) = ICC(avg) * VCC
Description : The phase constant of a wave propagation with frequency of 35 radian/sec and time delay of 7.5 sec is a) 4.66 b) 262.5 c) 46.6 d) 26.25
Last Answer : b) 262.5
Description : The reflection coefficient in the wave propagation when it is transmitted with the Brewster angle is a) 0 b) 1 c) -1 d) Infinity
Description : The work done in the power transmission with E and H given by 50 and 65 respectively. The velocity of propagation is 20m/s. a) 162.5 b) 621.5 c) 562.1 d) 261.5
Last Answer : a) 162.5
Description : The electric and magnetic field components in the electromagnetic wave propagation are in phase. State True/False. a) True b) False
Description : An example for electromagnetic wave propagation is a) refrigerator b) electric fan c) mobile transponder d) relays in actuators
Last Answer : c) mobile transponder
Description : The propagation constant of the wave in a conductor with air as medium is a) √(ωμσ) b) ωμσ c) √(ω/μσ) d) ω/μσ
Last Answer : a) √(ωμσ)
Description : The vectors of the electromagnetic wave propagation can be expressed in a) Dot product b) Cross product c) Unit vector d) Perpendicular vector
Last Answer : b) Cross product
Description : Calculate the velocity of wave propagation in a conductor with frequency 5 x 10 8 rad/s and phase constant of 3 x 10 8 units. a) 3/5 b) 15 c) 5/3 d) 8
Last Answer : c) 5/3
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 : The propagation of the electromagnetic waves can be illustrated by a) Faraday law b) Ampere law c) Flemming rule d) Coulomb law
Last Answer : c) Flemming rule
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 : Rectangular waveguides dominate the circular waveguides. Find the reason. a) Low cut-off frequency b) Easy to design c) More wave propagation d) The statement is false
Last Answer : b) Easy to design
Description : _______ is referred as the difference between available power and power budget? A. Fade margin B. Power margin C. Nominal gain D. Power dissipation
Last Answer : B. Power margin