Electromagnetic Theory and Transmission Lines Mid - I, February - 2011

1.The divergence theorem
  • relates a line integral to a surface integral.
  • holds for specific vector fields only
  • works for open surfaces
  • relates a surface integral to a volume integral
Answer: D
2.The unit of magnetic flux density is
  • Ampere
  • Tesla
  • Henries/meter
  • coulomb
Answer: B
3.The equivalent of ohms law for magnetic circuit is
  • J=σE
  • B=μH
  • H=-∇V
  • E=-∇V
Answer: A
4.Maxwell inserted the expression for displacement current JD=in ampere’s circuital law to satisfy
  • Ampere’s law for time varying fields
  • Faraday’s law
  • Gauss’s law
  • Equation of continuity
Answer: D
5.Which of the following eqation represents mathematical form of third maxwel l’s equation
  • ∇ × H =J2
  • ∇ . H = J
  • ∇^2. H = J
  • ∇ × H = J
Answer: D
6.Which of the following is not Maxwell equation
  • ∇.D=ρ
  • ∇XE=-dB/dt
  • ∇XH=J+dD/dt
  • ∇.J=-dρ/dt
Answer: D
7.Which of the following is a mathematically incorrect expression
  • grad div
  • grad curl
  • div curl
  • curl grad
Answer: C
8.Which of the following is zero?
  • grad div
  • curl grad
  • div grad
  • curl curl
Answer: C
9.For a dielectric –conductor interface the boundary condition that is not satisfied is
  • Et1=Et2
  • Dn1=0
  • Ht1=Ht2
  • Bn1=Bn2
Answer: C
10.∇� E = - ∂ B /∂ t is the mathematical form of
  • Gauss’s law
  • Faraday’s law
  • Ampere’s law
  • Coulomb’s l aw
Answer: B
11.For any material B _________
Answer: μoH
12.The permeability of free space is-------------
Answer: 4X10-7
13.Integral form of Ampere’s circuital law is ------------
Answer: _
14.The continuity equation is --------------
Answer: _
15.Point form of Faraday’s law ----------
Answer: ∇ × E = - ∂ B /∂ t
16.In case of time varying fields Gauss law is ______
Answer: ∇.D = ρv
17.Gauss’s law for magnetic field is -------------
Answer: ∇.B = 0
18.Units of Torque ___________
Answer: N.m
19. H.dl = ___________
Answer: Ienc
20.Poisson’s equation is -------------
Answer: (∇^2)V = v/E