Description : Find the magnitude of the displacement current density in air at a frequency of 18GHz in frequency domain. Take electric field E as 4 units. a) 18 b) 72 c) 36 d) 4
Last Answer : d) 4
Description : When the Maxwell equation is expressed in frequency domain, then which substitution is possible? a) d/dt = w/j b) d/dt = j/w c) d/dt = jw
Last Answer : c) d/dt = jw
Description : In dielectric medium, the Maxwell second equation becomes a) Curl(H) = Jd b) Curl(H) = Jc c) Curl(E) = Jd d) Curl(E) = Jd
Last Answer : a) Curl(H) = Jd
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 : 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
Last Answer : b) 0.5
Description : The charge build up in a capacitor is due to a) Conduction current density b) Displacement current density c) Polarisation d) Magnetization
Last Answer : b) Displacement current density
Description : At dc field, the displacement current density will be a) 0 b) 1 c) Jc d) ∞
Last Answer : a) 0
Description : Find the displacement current density of a material with flux density of 5sin t a) 2.5cos t b) 2.5sin t c) 5cos t d) 5sin t
Last Answer : c) 5cos t
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 displacement current when the flux density is given by t 3 at 2 seconds. a) 3 b) 6 c) 12 d) 27
Last Answer : c) 12
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 : Calculate the displacement current density when the electric flux density is 20sin 0.5t. a) 10sin 0.5t b) 10cos 0.5t c) 20sin 2t d) 20cos 2t
Last Answer : b) 10cos 0.5t
Description : The current in a metal at any frequency is due to a) Conduction current b) Displacement current c) Both conduction and displacement current d) Neither conduction nor displacement current
Last Answer : a) Conduction current
Description : The total current density is given as 0.5i + j – 1.5k units. Find the curl of the magnetic field intensity. a) 0.5i – 0.5j + 0.5k b) 0.5i + j -1.5k c) i – j + k d) i + j – k
Last Answer : b) 0.5i + j -1.5k
Description : Find the correct relation between current density and magnetization. a) J = Grad(M) b) J = Div(M) c) J = Curl(M) d) M = Curl(J)
Last Answer : c) J = Curl(M)
Description : Find current density J when B = 50 x 10-6 units and area dS is 4 units. a) 9.94 b) 8.97 c) 7.92 d) 10.21
Last Answer : b) 8.97
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 : Calculate the charge density for the current density given 20sin x i + ycos z j at the origin. a) 20t b) 21t c) 19t d) -20t
Last Answer : b) 21t
Description : Find the power, given energy E = 2J and current density J = x 2 varies from x = 0 and x = 1. a) 1/3 b) 2/3 c) 1 d) 4/3
Last Answer : b) 2/3
Description : Calculate the frequency at which the conduction and displacement currents become equal with unity conductivity in a material of permittivity 2. a) 18 GHz b) 9 GHz c) 36 GHz d) 24 GHz
Last Answer : b) 9 GHz
Description : On equating the generic form of current density equation and the point form of Ohm’s law, we can obtain V=IR. State True/False. a) True b) False
Last Answer : a) True
Description : An implication of the continuity equation of conductors is given by a) J = σ E b) J = E/σ c) J = σ/E d) J = jwEσ
Last Answer : a) J = σ E
Description : In metals which of the following equation will hold good? a) Curl(H) = J b) Curl(J) = dD/dt c) Curl(H) = D d) Curl(J) = dB/dt
Last Answer : a) Curl(H) = J
Description : Find the Maxwell equation derived from Faraday’s law. a) Div(H) = J b) Div(D) = I c) Curl(E) = -dB/dt d) Curl(B) = -dH/dt
Last Answer : c) Curl(E) = -dB/dt
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 : Both the conduction and displacement current densities coexist in which medium? a) Only conductors in air b) Only dielectrics in air c) Conductors placed in any dielectric medium d) Both the densities can never coexist
Last Answer : c) Conductors placed in any dielectric medium
Description : The charge build up in the capacitor is due to which quantity? a) Conduction current b) Displacement current c) Convection current d) Direct current
Last Answer : d) Direct current
Description : Find the flux density B when the potential is given by x i + y j + z k in air. a) 12π x 10 -7 b) -12π x 10 -7 c) 6π x 10 -7 d) -6π x 10 -7
Last Answer : b) -12π x 10 -7
Description : Find the magnetic flux density of the material with magnetic vector potential A = y i + z j + x k. a) i + j + k b) –i – j – k c) –i-j d) –i-k
Last Answer : b) –i – j – k
Description : Find the charge density when the electric flux density is given by 2x i + 3y j + 4z k. a) 10 b) 9 c) 24 d) 0
Last Answer : b) 9
Description : The Gauss law employs which theorem for the calculation of charge density? a) Green theorem b) Stokes theorem c) Gauss theorem d) Maxwell equation
Last Answer : c) Gauss theorem
Description : The current element of the magnetic vector potential for a surface current will be a) J dS b) I dL c) K dS d) J dV
Last Answer : c) K dS
Description : The magnetic vector potential for a line current will be inversely proportional to a) dL b) I c) J d) R
Last Answer : d) R
Description : Calculate the Larmer angular frequency for a magnetic flux density of 12.34 x 10 -10 . a) 108.36 b) 810.63 c) 368.81 d) 183.36
Last Answer : a) 108.36
Description : From the formula F = qE, can prove that work done is a product of force and displacement. State True/False a) True b) False
Description : If Laplace equation satisfies, then which of the following statements will be true? a) Potential will be zero b) Current will be infinite c) Resistance will be infinite d) Voltage will be same
Last Answer : b) Current will be infinite
Description : Calculate the conduction current density when the resistivity of a material with an electric field of 5 units is 4.5 units. a) 22.5 b) 4.5/5 c) 5/4.5 d) 9.5
Last Answer : c) 5/4.5
Description : The magnitude of the conduction current density for a magnetic field intensity of a vector yi + zj + xk will be a) 1.414 b) 1.732 c) -1.414 d) -1.732
Last Answer : b) 1.732
Description : Find the conduction current density of a material with conductivity 200units and electric field 1.5 units. a) 150 b) 30 c) 400/3 d) 300
Last Answer : d) 300
Description : The line integral of the magnetic field intensity is the a) Current density b) Current c) Magnetic flux density d) Magnetic moment
Last Answer : b) Current
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 : 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 : 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 : Ampere law states that, a) Divergence of H is same as the flux b) Curl of D is same as the current c) Divergence of E is zero d) Curl of H is same as the current density
Last Answer : d) Curl of H is same as the current density
Description : Find the magnetic field intensity when the current density is 0.5 units for an area up to 20 units. a) 10 b) 5 c) 20 d) 40