Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
EM waves do not travel inside metals. State True/False.
a Explanation: The conductors or metals do not support EM wave propagation onto them due the skin effect. This is the reason why mobile phones cannot be used inside lifts.
a
See lessExplanation: The conductors or metals do not support EM wave propagation onto them due the skin effect. This is the reason why mobile phones cannot be used inside lifts.
In conductors, the E and H vary by a phase difference of
c Explanation: The electric and magnetic component, E and H respectively have a phase difference of 45 degrees. This is due to the wave propagation in conductors in the air medium.
c
See lessExplanation: The electric and magnetic component, E and H respectively have a phase
difference of 45 degrees. This is due to the wave propagation in conductors in the air
medium.
The expression for velocity of a wave in the conductor is
a Explanation: The velocity is the ratio of the frequency to the phase constant. In conductors, the phase constant is given by √(ωμσ/2). On substituting for β,ω in v, we get v = √(2ω/μσ) units.
a
See lessExplanation: The velocity is the ratio of the frequency to the phase constant. In
conductors, the phase constant is given by √(ωμσ/2). On substituting for β,ω in v, we get v = √(2ω/μσ) units.
The skin depth of a conductor with attenuation constant of 7 neper/m is
d Explanation: The skin depth is the measure of the depth upto which an EM wave can penetrate through the conductor surface. It is the reciprocal of the attenuation constant. On substituting for α = 7, we get δ = 1/α = 1/7 units.
d
See lessExplanation: The skin depth is the measure of the depth upto which an EM wave can
penetrate through the conductor surface. It is the reciprocal of the attenuation constant. On substituting for α = 7, we get δ = 1/α = 1/7 units.
Calculate the attenuation constant of a conductor of conductivity 200 units, frequency 1M radian/s in air.
a Explanation: The attenuation constant of a conductor is given by α = √(ωμσ/2). On substituting ω = 106, σ = 200 and μ = 4π x 10-7, we get α = 11.2 units.
a
See lessExplanation: The attenuation constant of a conductor is given by α = √(ωμσ/2). On
substituting ω = 106, σ = 200 and μ = 4π x 10-7, we get α = 11.2 units.
Calculate the phase constant of a conductor with attenuation constant given by 0.04 units.
d Explanation: The phase constant and the attenuation constant are both the same in the case of conductors. Given that the attenuation constant is 0.04, implies that the phase constant is also 0.04.
d
See lessExplanation: The phase constant and the attenuation constant are both the same in the case of conductors. Given that the attenuation constant is 0.04, implies that the phase constant is also 0.04.
The total permeability in a conductor is
c Explanation: The total permeability is the product of the absolute and the relative permeability. For metals or conductors, the relative permittivity is not unity. Thus the permittivity is the product of absolute and relative permeability.
c
See lessExplanation: The total permeability is the product of the absolute and the relative
permeability. For metals or conductors, the relative permittivity is not unity. Thus the
permittivity is the product of absolute and relative permeability.
In metals, the total permittivity is
a Explanation: The total permittivity is the product of the absolute and the relative permittivity. For metals or conductors, the relative permittivity is unity. Thus the permittivity is simply the absolute permittivity.
a
See lessExplanation: The total permittivity is the product of the absolute and the relative
permittivity. For metals or conductors, the relative permittivity is unity. Thus the
permittivity is simply the absolute permittivity.
For conductors, the loss tangent will be
c Explanation: In conductors, the conductivity will be more. Thus the loss tangent σ/ωε will be maximum.
c
See lessExplanation: In conductors, the conductivity will be more. Thus the loss tangent σ/ωε will be maximum.
The vectors of the electromagnetic wave propagation can be expressed in
b Explanation: In an EM wave, the electric and the magnetic fields will be perpendicular to each other and with the direction of the propagation. Thus it can be expressed in cross product where iE x iH = iw. Here iE is the electric vector component, iH is the magnetic vector component and iw is theRead more
b
See lessExplanation: In an EM wave, the electric and the magnetic fields will be perpendicular to each other and with the direction of the propagation. Thus it can be expressed in cross product where iE x iH = iw. Here iE is the electric vector component, iH is the magnetic vector component and iw is the vector of the wave propagating.