Description : A perfect dielectric acts as a a) Perfect transmitter b) Perfect reflector c) Bad transmitter d) Bad reflector
Last Answer : a) Perfect transmitter
Description : The angle of incidence is equal to the angle of reflection for perfect reflection. State True/False. a) True b) False
Last Answer : a) True
Description : The loss tangent of a perfect dielectric will be a) Zero b) Unity c) Maximum d) Minimum
Last Answer : d) Minimum
Description : In perfect conductors, the phase shift between the electric field and magnetic field will be a) 0 b) 30 c) 45 d) 90
Last Answer : c) 45
Description : For a perfect dielectric, which parameter will be zero? a) Conductivity b) Frequency c) Permittivity d) Permeability
Last Answer : a) Conductivity
Description : Calculate the skin depth of a conductor, having a conductivity of 200 units. The wave frequency is 10 GHz in air. a) 355.8 b) 3.558 c) 35.58 d) 0.3558
Last Answer : a) 355.8
Description : The skin depth of a wave with phase constant of 12 units inside a conductor is a) 12 b) 1/12 c) 24 d) 1/24
Last Answer : b) 1/12
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 expression for velocity of a wave in the conductor is a) V = √(2ω/μσ) b) V = √(2ωμσ) c) V = (2ω/μσ) d) V = (2ωμσ)
Last Answer : a) V = √(2ω/μσ)
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 total permeability in a conductor is a) Absolute permeability b) Relative permeability c) Product of absolute and relative permeability d) Unity
Last Answer : c) Product of absolute and relative permeability
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 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 : The Gauss law for magnetic field is valid in a) Air b) Conductor c) Dielectric d) All cases
Last Answer : d) All cases
Description : The Maxwell second equation that is valid in any conductor is a) Curl(H) = Jc b) Curl(E) = Jc c) Curl(E) = Jd d) Curl(H) = Jd
Last Answer : a) Curl(H) = Jc
Description : The torque expression of a current carrying conductor is a) T = BIA cos θ b) T = BA cos θ c) T = BIA sin θ d) T = BA sin θ
Last Answer : c) T = BIA sin θ
Description : Calculate the flux density due to a circular conductor of radius 100nm and current 5A in air. a) 10 b) 100 c) 0.1 d) 1
Last Answer : a) 10
Description : Find the Lorentz force due to a conductor of length 2m carrying a current of 1.5A and magnetic flux density of 12 units. a) 24 b) 36 c) 32 d) 45
Last Answer : c) 32
Description : The torque of a conductor is defined only in the case when a) The field is perpendicular to the loop b) The plane of the loop is parallel to the field c) The plane of the loop is perpendicular to the current direction d) The field and the current direction are same
Last Answer : b) The plane of the loop is parallel to the field
Description : Consider the conductor to be a coil of turns 60 and the flux density to be 13.5 units, current 0.12A and area 16units. The torque will be a) 1555.2 b) 1222.5 c) 525.1 d) 255.6
Last Answer : a) 1555.2
Description : The torque on a conductor with flux density 23 units, current 1.6A and area 6.75 units will be a) 248.4 b) 192.6 c) 175.4 d) 256.9
Last Answer : a) 248.4
Description : The distance of the conductor when the area and length of the conductor is 24m2 and 13.56m. a) 1.76 b) 2.67 c) 1.52 d) 2.15
Last Answer : a) 1.76
Description : Find the maximum force of the conductor having length 60cm, current 2.75A and flux density of 9 units. a) 14.85 b) 18.54 c) 84.25 d) 7.256
Last Answer : a) 14.85
Description : Find the flux density due to a conductor of length 6m and carrying a current of 3A(in 10 -7 order) a) 1 b) 10 c) 100 d) 0.1
Last Answer : a) 1
Description : The force on a conductor of length 12cm having current 8A and flux density 3.75 units at an angle of 300 is a) 1.6 b) 2 c) 1.4 d) 1.8
Last Answer : d) 1.8
Description : Find the flux density of a conductor in the square of the centre of the loop having current 3.14A and radius is 1.414m in air. a) 8π x 10 -7 b) 4π x 10 -7 c) 6π x 10 -7 d) 2π x 10 -7
Last Answer : c) 6π x 10 -7
Description : Find the force experienced by an electromagnetic wave in a conductor? a) Electrostatic force b) Magneto static force c) Electro motive force d) Lorentz force
Last Answer : d) Lorentz force
Description : Find the height of an infinitely long conductor from point P which is carrying current of 6.28A and field intensity is 0.5 units. a) 0.5 b) 2 c) 6.28 d) 1
Last Answer : b) 2
Description : Find the current density on the conductor surface when a magnetic field H = 3cos x i + zcos x j A/m, for z>0 and zero, otherwise is applied to a perfectly conducting surface in xy plane. a) cos x i b) –cos x i c) cos x j d) –cos x j
Last Answer : b) –cos x i
Description : Find the magnetic flux density of a finite length conductor of radius 12cm and current 3A in air( in 10 -6 order) a) 4 b) 5 c) 6 d) 7
Last Answer : b) 5
Description : Electric field will be maximum outside the conductor and magnetic field will be maximum inside the conductor. State True/False. a) True b) False
Description : Find the magnetic field when a circular conductor of very high radius is subjected to a current of 12A and the point P is at the centre of the conductor. a) 1 b) ∞ c) 0 d) -∞
Last Answer : c) 0
Description : The magnetic field intensity will be zero inside a conductor. State true/false. a) True b) False
Last Answer : b) False
Description : Calculate the magnetic field at a point on the centre of the circular conductor of radius 2m with current 8A. a) 1 b) 2 c) 3 d) 4
Description : The charge within a conductor will be a) 1 b) -1 c) 0 d) ∞
Description : Calculate the potential when a conductor of length 2m is having an electric field of 12.3units. a) 26.4 b) 42.6 c) 64.2 d) 24.6
Last Answer : d) 24.6
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 : 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 : A dielectric can be made a conductor by a) Compression b) Heating c) Doping d) Freezing
Last Answer : b) Heating
Description : Which of the following properties distinguish a material as conductor, insulator and semiconductor? a) Free electron charges b) Fermi level after doping c) Energy band gap d) Electron density
Last Answer : c) Energy band gap
Description : Find the force on a conductor of length 12m and magnetic flux density 20 units when a current of 0.5A is flowing through it. a) 60 b) 120 c) 180 d) 200
Last Answer : b) 120
Description : Find the current in a conductor with resistance 2 ohm, electric field 2 units and distance 100cm. a) 1A b) 10mA c) 10A d) 100mA
Last Answer : a) 1A
Description : Electric field of an infinitely long conductor of charge density λ, is given by E = λ/(2πεh).aN. State True/False. a) True b) False
Description : A white and smooth surface is – (1) good absorber and good reflector of heat (2) bad absorber and good reflector of heat (3) good absorber and bad reflector of heat (4) bad absorber and bad reflector of heat
Last Answer : (2) bad absorber and good reflector of heat Explanation: Shiny surfaces are poor absorbers of heat radiation and the best reflectors of heat radiation. Black surfaces are the best emitters and best absorber of heat radiation.
Description : The earth is a – (1) good reflector of heat (2) non-absorber of heat (3) good absorber and good radiator of heat (4) bad absorber and bad radiator of heat
Last Answer : (3) good absorber and good radiator of heat Explanation: The earth's surface radiates as a black body, since it aborts and radiates with nearly 100 percent efficiency for its temperatures. Gases, on the contrary, are selective absorbers and radiators.
Description : A white and smooth surface is (1) good absorber and good reflector of heat (2) bad absorber and good reflector of heat (3) good absorber and bad reflector of heat (4) bad absorber and bad reflector of heat
Last Answer : bad absorber and good reflector of heat
Description : The earth is a (1) good reflector of heat (2) non-absorber of heat (3) good absorber and good radiator of heat (4) bad absorber and bad radiator of heat
Last Answer : Bad absorber and bad radaitor because all bad absorber are bad emitter. As well