Electromagnetism mcq questions answers part2

Q1. ......is the reflection co-efficient of an open circuited transmission line
(A) zero
(B) -1
(C) 1
(D) none of these

Q2. A rectangular waveguide act as:
(A) Low pass filter
(B) High pass filter
(C) Bandpass filter
(D) Bandstop filter

Q3. As a result of reflection from a plane conducting wall, electromagnetic waves acquire an apparent velocity greater than the velocity of light in space. This is called the
(A) group velocity
(B) normal velocity
(C) phase velocity
(D) velocity of propagation

Q4. Assuming perfect conductor of transmission line, pure TEM propagation is not possible in
(A) Parallel thin wire line
(B) Coaxial cable
(C) Air filled cylindrical waveguide
(D) Semi-infinite parallel wave guide

Q5. Between a hollow and solid metal sphere, charge reside
(A) On outer surface in both
(B) On outer surface in hollow and throughout is solid
(C) On outer surface in solid and throughout hollow
(D) None of these

Q6. For a cylindrical waveguide, dominant mode is:
(A) TE01
(B) TM01
(C) TE11
(D) TM11

Q7. In a waveguide the operating wavelength is less than cut-off wavelength, the wave will be:
(A) Guided
(B) Attenuated
(C) Guided with attenuation
(D) Not propagated at all

Q8. In case of matched load
(A) Transmission is zero
(B) reflection is zero
(C) reflection is unity
(D) transmission is equivalent to reflection

Q9. Inside a hollow conducting sphere
(A) electric field is zero
(B) electric field is a non zero constant
(C) electric field changes with magnitude of the charge given to the conductor
(D) electric field changes with distance from the center of the sphere

Q10. Lenz law is the consequence of the law of conservation of
(A) Momentum
(B) Energy
(C) Charge
(D) None of these

Q11. Permeability is the inverse equivalent of which electrical term?
(A) Resistance
(B) Conductance
(C) current
(D) voltage

Q12. The ability of a material to conduct magnetic flux through it.
(A) Permeability
(B) Permittivity
(C) Conductivity
(D) Reluctivity

Q13. The current of electric circuit is analogous to which quantity of a magnetic circuit
(A) Mmf
(B) Flux density
(C) Flux
(D) Reluctivity

Q14. The cut off frequency of a wave guide means
(A) lower frequencies will not be propagated
(B) it determines the dimensions of the wave guide
(C) frequency at which zero transmission takes place
(D) None of above

Q15. The direction of the induced emf and hence current always opposes the cause producing it. This is known as:
(A) Newton’s first law
(B) Lenz law
(C) Ampere’s Law
(D) Coulomb’s Law

Q16. The dominant mode for TM waves in a waveguide is:
(A) TE01
(B) TM01
(C) TE11
(D) TM11

Q17. The dominate mode of propagation in microstrip line in low frequency approximation
(A) tm11
(B) tem
(C) te01
(D) quasi TEM

Q18. The emf induced in a coil due to the change of its own flux linked with it is called
(A) Self induced emf
(B) Mutual induced emf
(C) Dynamically induced emf
(D) Statically induced emf

Q19. The emf induced in a coil due to the changing current of another neighboring coil is called
(A) Self induced emf
(B) Dynamically induced emf
(C) Statically induced emf
(D) Mutually induced emf

Q20. The magnetic potential in a magnetic circuit can be measured in terms of
(A) Emf
(B) Current
(C) Mmf
(D) Voltage

Q21. The magnitude of the induced emf in a coil is directly proportional to the rate of change of flux linkages. This is known as
(A) Joule’s Law
(B) Ampere’s Law
(C) Faraday’s second law of electromagnetic induction
(D) Coulomb’s Law

Q22. The net electrical charge in an isolated system remains constant. This is known as
(A) Coulomb’s first law
(B) Law of conservation of charge
(C) Coulomb’s second law
(D) Law of conservation of energy

Q23. The phenomenon by which a magnetic substance becomes a magnet when it is place near a magnet
(A) Magnetic effect
(B) Magnetic induction
(C) Electromagnetic induction
(D) Magnetic theory

Q24. The property of a material which opposes the creation of magnetic flux in it
(A) Resistance
(B) Reluctance
(C) Admittance
(D) Conductance

Q25. The reciprocal of reluctance :
(A) Permeance
(B) Resistance
(C) Inductance
(D) Conductance