Electromagnetic Field Theory

mcqspedia.com has 274 Question/Answers about Topic Electromagnetic Field Theory

The function f(x – vot) represent which of the following?

The function f(x – vot) represent which of the following?
  • A. A stationary wave
  • B. A wave motion in forward direction
  • C. A wave motion in reverse direction
  • D. None of the above
  • Correct Answer: Option B

Which of the following should dominant wave have?

Which of the following should dominant wave have?
  • A. Lowest cut off frequency
  • B. Highest cut off frequency
  • C. No attenuation
  • D. No phase shift
  • Correct Answer: Option A

__________ will have the least value of relative permeability.

__________ will have the least value of relative permeability.
  • A. Palladium
  • B. Silver
  • C. Cobalt
  • D. Iron
  • Correct Answer: Option B

A dominant wave is characterised by which of the following?

A dominant wave is characterised by which of the following?
  • A. No attenuation
  • B. Lowest cut off wavelength
  • C. Highest cut off wavelength
  • D. All of the above
  • Correct Answer: Option C

The value of susceptibility in case of vacuum is taken as

The value of susceptibility in case of vacuum is taken as
  • A. zero
  • B. 0.5
  • C. unity
  • D. infinity
  • Correct Answer: Option A

Poynting vector is associated with which of the following?

Poynting vector is associated with which of the following?
  • A. Power flow in electromagnetic
  • B. Flux in magnetic field
  • C. Charge in electrostatic field
  • D. Current in electrostatic field
  • Correct Answer: Option A

Conductivity is measured in terms of

Conductivity is measured in terms of
  • A. mho/metre
  • B. ohm/metre
  • C. mho/metre2
  • D. ohm/metre2
  • Correct Answer: Option A

The static electric field in a conductor is

The static electric field in a conductor is
  • A. zero
  • B. unity
  • C. infinity
  • D. none of the above
  • Correct Answer: Option A

Which of the following are the properties of a medium?

Which of the following are the properties of a medium?
  • A. Permeability, flux, magnesium
  • B. Permittivity, permeability, insulation
  • C. Permeability, resistivity, conductivity
  • D. Permittivity, permeability, conductivity
  • Correct Answer: Option D

Poynting vector signifies which of the following?

Poynting vector signifies which of the following?
  • A. Power density vector producing electrostatic field
  • B. Power density vector producing electromagnetic field
  • C. Current density vector producing electrostatic field
  • D. Current density vector producing electromagnetic field
  • Correct Answer: Option B

The attenuation in a waveguide near the cut off frequency is

The attenuation in a waveguide near the cut off frequency is
  • A. zero
  • B. low
  • C. high
  • D. very high
  • Correct Answer: Option A

The waveguides compared to equivalent transmission lines at low frequency are

The waveguides compared to equivalent transmission lines at low frequency are
  • A. able to carry more power
  • B. less noisy
  • C. having lower attenuation
  • D. all of the above
  • Correct Answer: Option D

Which of the following is the main difference between waveguide and transmission line?

Which of the following is the main difference between waveguide and transmission line?
  • A. Waveguides cannot be coupled to coaxial lines
  • B. Waveguides have no standing wave ratio
  • C. Transmission line does not suffer from the effect of low cut off frequency
  • D. Waveguides are not distributed like transmission lines
  • Correct Answer: Option C

The simplest standing wave is due to the value of reflection co-efficient is

The simplest standing wave is due to the value of reflection co-efficient is
  • A. -1
  • B. zero
  • C. unity
  • D. infinity
  • Correct Answer: Option C

For a distortionless line, the parameters are related as

For a distortionless line, the parameters are related as
  • A. R/G = L/C
  • B. R/L = 1
  • C. R/G = C/L
  • D. RG = LC
  • Correct Answer: Option A

A rectangular waveguide is a

A rectangular waveguide is a
  • A. rectangular conducting wire to propagate electromagnetic waves
  • B. hollow rectangular walled room carrying electromagnetic wave
  • C. hollow rectangular conducting tube through which electromagnetic waves can be propagated
  • D. tube antenna to transmit and receive electromagnetic waves
  • Correct Answer: Option C

Short-circuited stubs are used, because open-circuited stubs are

Short-circuited stubs are used, because open-circuited stubs are
  • A. liable to radiate
  • B. complex in nature
  • C. providing open-circuit environments
  • D. unable to provide work over large frequency range
  • Correct Answer: Option A

Which of the following statements is incorrect regarding Balun transformer?

Which of the following statements is incorrect regarding Balun transformer?
  • A. It changes impedance like current transformer
  • B. It changes balanced to unbalanced line
  • C. It is used to couple a co-axial line to a parallel line wire
  • D. Any of the above
  • Correct Answer: Option A

Which of the following impedance inversion is obtained?

Which of the following impedance inversion is obtained?
  • A. Short-circuited stub
  • B. A quarter wave line
  • C. Balun transformer
  • D. A half wave line
  • Correct Answer: Option B

For infinite value of SWR on a transmission line, the line be terminated with impedance as

For infinite value of SWR on a transmission line, the line be terminated with impedance as
  • A. an open-circuit
  • B. a short-circuit
  • C. a pure resistance
  • D. all of the above
  • Correct Answer: Option D