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This set of Electromagnetics Multiple Choice Questions & Answers (MCQs) focuses on Electromagnetics Set 6
Q1 | Find the susceptibility of a material whose dielectric constant is 2.26.
- 1.26
- 3.26
- 5.1
- 1
Q2 | The susceptibility of free space is
- 1
- 0
- 2
- ∞
Q3 | When the electric field becomes zero, which of the following relations hold good?
- e = p
- d = p
- b = p
- h = p
Q4 | Which of the following are conductors?
- ceramics
- plastics
- mercury
- rubber
Q5 | Find the range of band gap energy for conductors.
- >6 ev
- 0.2-0.4 ev
- 0.4-2 ev
- 2-6 ev
Q6 | Conduction in metals is due to
- electrons only
- electrons and holes
- holes only
- applied electric field
Q7 | Find the band gap energy when a light of wavelength 1240nm is incident on it.
- 1ev
- 2ev
- 3ev
- 4ev
Q8 | Alternating current measured in a transmission line will be
- peak value
- average value
- rms value
- zero
Q9 | The current in a metal at any frequency is due to
- conduction current
- displacement current
- both conduction and displacement current
- neither conduction nor displacement current
Q10 | For conductors, the free electrons will exist at
- valence band
- middle of valence and conduction band
- will not exist
- conduction band
Q11 | The current flowing through an insulating medium is called
- conduction
- convection
- radiation
- susceptibility
Q12 | Identify a good dielectric.
- iron
- ceramics
- plastic
- magnesium
Q13 | A dielectric can be made a conductor by
- compression
- heating
- doping
- freezing
Q14 | Find the dielectric constant for a material with electric susceptibility of 4.
- 3
- 5
- 8
- 16
Q15 | For a dielectric which of the following properties hold good?
- they are superconductors at high temperatures
- they are superconductors at low temperatures
- they can never become a superconductor
- they have very less dielectric breakdown voltage
Q16 | he magnetic field which destroys the superconductivity is called
- diamagnetic field
- ferromagnetic field
- ferrimagnetic field
- critical field
Q17 | The magnetic susceptibility in a superconductor will be
- positive
- negative
- zero
- infinity
Q18 | The superconducting materials will be independent of which of the following?
- magnetic field
- electric field
- magnetization
- temperature
Q19 | Find the mean free path of an electron travelling at a speed of 18m/s in 2 seconds.
- 9
- 36 c) 0.11 d) 4.5
Q20 | The best definition of polarisation is
- orientation of dipoles in random direction
- electric dipole moment per unit volume
- orientation of dipole moments
- change in polarity of every dipole
Q21 | Polarizability is defined as the
- product of dipole moment and electric field
- ratio of dipole moment to electric field
- ratio of electric field to dipole moment
- product of dielectric constant and dipole moment
Q22 | Identify which type of polarisation depends on temperature.
- electronic
- ionic
- orientational
- interfacial
Q23 | The total polarisation of a material is the
- product of all types of polarisation
- sum of all types of polarisation
- orientation directions of the dipoles
- total dipole moments in the material
Q24 | In the given types of polarisation, which type exists in the semiconductor?
- electronic
- ionic
- orientational
- interfacial or space charge
Q25 | Solids do not have which type of polarisation?
- ionic
- orientational
- interfacial
- electronic