A parallel polarized wave is incident from air into paraffin having relative permittivity 3, the value of its Brewster angle is:60°
Description : Find the permittivity of the surface when a wave incident at an angle 60 is reflected by the surface at 45 in air. a) 1.41 b) 3.5 c) 2.2 d) 1.73
Last Answer : d) 1.73
Description : An elliptically (arbitrarily polarized wave c an be broken up into a) Two circularly polarized components rotating in same direction b) Two circularly polarized components rotating in opposite directions c) Two stationary circularly polarized components d) None of these
Last Answer : An elliptically (arbitrarily polarized wave c an be broken up into Two circularly polarized components rotating in opposite directions
Description : The velocity of travelling wave through a cable of relative permittivity 36 is
Last Answer : The velocity of travelling wave through a cable of relative permittivity 36 is 0.5 x 108 m/sec
Description : Find the relative permittivity of the medium having a refractive index of 1.6 a) 0.4 b) 2.56 c) 3.2 d) 4.8
Last Answer : b) 2.56
Description : Three materials X, Y and Z having relative permittivity 2.5, 3.0 and 4.0 respectively are used in a single core cable. The materials on inner most and outer most layer respectively should be (a) X and Y (b) Y and Z (c) X and Z (d) Z and X
Last Answer : Answer is option d Because the material with high relative permitivity should be used as the inner most layer of the cable,to withstand with the high currents flowing in the conductor
Description : A radio signal moves from air to glass. The angle of incidence is 20°. Calculate the angle of refraction. The relative permittivity of the glass is 7.8. A. 7.8° B. 5.04° C. 6.04° D. 7.04°
Last Answer : D. 7.04°
Description : Which parameter is unity in air medium? a) Permittivity b) Absolute permeability c) Relative permeability d) Permeability
Last Answer : c) Relative permeability
Description : Pick up the correct statement from the following: (A) The surface defined by the locus of points having same phase, is called a wave front (B) The wave whose surface of constant phase are parallel planes, ... waves is important and not the absolute phase of a point on the wave (D) All of these
Last Answer : Answer: Option D
Description : A cylindrical cable of core radius 1.25cm and impregnated paper insulation of thickness 2.13cm and relative permittivity 3.5. Compute the capacitance of the cable/km (in nF
Last Answer : To calculate the capacitance of the cable per kilometer, you can use the following formula: C = ε * ε0 * A / d where: C is the capacitance of the cable per kilometer (in farads) ε is ... * 10^9 = 644 nF/km So the capacitance of the cable per kilometer would be approximately 644 nanofarads.
Description : The total permittivity of a dielectric transformer oil (relative permittivity is 2.2) will be (in order 10 -11 ) a) 1.94 b) 19.4 c) 0.194 d) 194
Last Answer : a) 1.94
Description : In metals, the total permittivity is a) Absolute permittivity b) Relative permittivity c) Product of absolute and relative permittivity d) Unity
Last Answer : a) Absolute permittivity
Description : In free space, which parameter will be unity? a) Permittivity b) Absolute permittivity c) Relative permittivity d) Permeability
Last Answer : c) Relative permittivity
Description : A cable of core radius 1.25cm and impregnated paper insulation of thickness 2.13cm and relative permittivity 3.5. Compute the capacitance of the cable/km(in nF) a) 195.7 b) 179.5 c) 157.9 d) 197.5
Last Answer : a) 195.7
Description : Choose the best definition of dielectric loss. a) Absorption of electric energy by dielectric in an AC field b) Dissipation of electric energy by dielectric in a static field c) Dissipation of heat by dielectric d) Product of loss tangent and relative permittivity
Last Answer : a) Absorption of electric energy by dielectric in an AC field
Description : A certain cable has an insulation of relative permittivity 4. If the insulation is replaced by one of relative permittivity 2, the capacitance of the cable will become (a) one half (6) double (c) four times (d) none of the above
Last Answer : (a) one half
Description : The relative permittivity of rubber is (a) between 2 and 3 (b) between 5 and 6 (c) between 8 and 10 (d) between 12 and 14
Last Answer : (a) between 2 and 3
Description : A material has conductivity of 10–2 mho/m and relative permittivity of 4. The frequency at which the conduction current in the medium is equal to the displacement current, is (a) 450 MHz (b) 900 MHz (c) 45 MHz (d) 90 MHz
Last Answer : C
Description : A cable has an insulation of relative permittivity 2. If the insulation is replaced by one of relative permittivity 4, then capacitance of the cable (a) is doubled (b) is halved (c) remains unchanged (d) is reduced
Last Answer : B
Description : The bridge most suited for accurate measurement of relative permittivity of dielectric materials is (A) Carey Foster Bridge (B) Anderson’s bridge (C) Heaviside Bridge modified by Campbell. (D) Schering Bridge.
Last Answer : The bridge most suited for accurate measurement of relative permittivity of dielectric materials is Schering Bridge.
Description : A 70-year-old patient presented with weakness, tiredness and muscle cramps. The ECG showed Q-T prolongation, flattening of T wave and occasional A-V block. His serum K+ was low (2.8 mEq ... could be responsible for the above condition: A. Bisacodyl B. Liquid paraffin C. Methylcellulose D. Bran
Last Answer : A. Bisacodyl
Description : Find the Brewster angle of a wave transmitted from a medium of permittivity 4 to a medium of permittivity 2. a) 35.26 b) 53.62 c) 26.35 d) 62.53
Last Answer : a) 35.26
Description : An electromagnetic wave is ________ polarized when the electric field lies wholly in one plane containing the direction of propagation. A. Horizontally B. Linearly C. Circularly D. Vertically
Last Answer : B. Linearly
Description : Of the following, the type of wave that CANNOT be polarized is w) electromagnetic x) light y) sound z) radio
Last Answer : ANSWER: Y -- SOUND
Description : An electromagnetic wave is ALWAYS: w) longitudinal x) polarized y) spherical z) transverse.
Last Answer : ANSWER: Z -- TRANSVERSE
Description : A wave incident on a surface at an angle 60 degree is having field intensity of 6 units. The reflected wave is at an angle of 30 degree. Find the field intensity after reflection. a) 9.4 b) 8.4 c) 10.4 d) 7.4
Last Answer : c) 10.4
Description : When a transmission line has a load impedance same as that of the characteristic impedance, the line is said to be a) Parallel b) Perpendicular c) Polarized d) Matched
Last Answer : Ans: D
Description : What is meant by referring to electromagnetic waves as horizontally polarized? A. The electric field is parallel to the earth. B. The magnetic field is parallel to the earth. C. Both the electric and magnetic fields are horizontal D. Both the electric and magnetic fields are vertical
Last Answer : A. The electric field is parallel to the earth.
Description : What is meant by referring to electromagnetic waves as horizontally polarized? A. The electric field is parallel to the earth B. Both the electric and magnetic fields are vertical C. Both the electric and magnetic fields are horizontal D. The magnetic fields is parallel to the earth
Last Answer : A. The electric field is parallel to the earth
Description : 13. A ray of light, incident obliquely on a face of a rectangular glass slab placed in air, emerges from the opposite face parallel to the incident ray. State two factors on which the lateral displacement of the emergent ray depends. [Foreign] -Chemistry-10
Last Answer : Lateral displacement depends on the: angle of incidence, thickness of slab, and refractive index of the material. (any two)
Description : Name the hydrocarbon having the poorest oxidation stability. (A) Naphthene (B) Olefin (C) Paraffin (D) Aromatics
Last Answer : (D) Aromatics
Description : Pick out the wrong statement. (A) Alkylation produces a larger iso-paraffin (having higher octane number) from the reaction of an olefin with smaller iso-paraffin (B) Catalytic alkylation processes use HF ... (> 1000°C) (D) Gasoline having an octane number of 90 can be produced by alkylation process
Last Answer : (C) All the alkylation processes use very high temperature (> 1000°C)
Description : Calorific value of (A) Light paraffinic fuel oils is equal to that of equivalent olefins (B) n-paraffin is lower than that of iso-paraffins of the same compounds (C) Light paraffinic fuel ... than that of equivalent olefins (D) Light paraffinic fuel oils is lower than that of equivalent olefins
Last Answer : (C) Light paraffinic fuel oils is higher than that of equivalent olefins
Description : The permeability and permittivity of air or free space is unity. State true/false. a) True b) False
Last Answer : a) True
Description : The electric field intensity of a surface with permittivity 3.5 is given by 18 units. What the field intensity of the surface in air? a) 5.14 b) 0.194 c) 63 d) 29
Last Answer : c) 63
Description : The electric flux density of a surface with permittivity of 2 is given by 12 units. What the flux density of the surface in air? a) 24 b) 6 c) 1/6 d) 0
Last Answer : b) 6
Last Answer : The velocity of the wave as it passes from air into ionosphere Increases.
Description : Which of these waves can be polarized? (1) Sound waves in air (2) Longitudinal waves on a string (3) Transverse waves on a string (4) Light waves
Last Answer : (4) Light waves Explanation: It is possible to transform unpolarized light into polarized light. A light. wave that is vibrating in more than one plane is referred to as unpolarized light. Polarized light waves are light waves in which the vibrations occur in a single plane.
Description : Which of these waves can be polarized ? (1) Sound waves in air (2) Longitudinal waves on a string (3) Transverse waves on a string (4) Light waves
Last Answer : Light waves
Description : An AC supply of 230 V is applied to a half-wave rectifier circuit through a transformer having primary to secondary turn’s ratio 12:1. The peak inverse voltage is A) 8.62 V B) 12 V C) 19.17 V D) 27.11 V
Last Answer : An AC supply of 230 V is applied to a half-wave rectifier circuit through a transformer having primary to secondary turn’s ratio 12:1. The peak inverse voltage is A) 8.62 V B) 12 V C) 19.17 V D) 27.11 V
Description : The sinusoidal wave `y(x,t) = ym sin(kx-omegat)` is incident on the fixed end of a string at `x = L`. The reflected wave is given by :-
Last Answer : The sinusoidal wave `y(x,t) = ym sin(kx-omegat)` is incident on the fixed end of a string at `x = L` ... (kx+omegat-kL)` D. `y_(m)sin(kx+omegat-2kL)`
Description : A light wave is incident over a plane surface with velocity x. After reflection the velocity becomes- (1) x/2 (2) x (3) 2x (4) x/4
Last Answer : (2) x Explanation: When a ray of light incident on a boundary separating two media comes back into the same media, this phenomenon, is called reflection of light. After reflection velocity, wavelength and frequency of light remains same but intensity decreases.
Description : The transmission coefficient of a wave with incident and transmitted electric field of 5 and 5 respectively is a) 0 b) 1 c) 10 d) 5
Last Answer : b) 1
Description : Find the reflection coefficient of a wave with an incident electric field of 5 units and reflected electric field of 2 units. a) 2.5 b) 0.4 c) 0.8 d) 1.2
Last Answer : b) 0.4
Description : An Electromagnetic wave falls on to a boundary between two losses less homogeneous media with different refractive indices, a part of the wave is reflected back to the incident medium and the rest is transmitted ... A) Fresnel reflection (B) Fresnel refraction (C) Snell's law (D) None of these
Last Answer : Answer: Option A
Description : According to the Snell's law if an electromagnetic wave is incident in a medium (refractive index n1) on another medium (refractive index m2); (A) The angle of incidence is equal to the angle of refraction (B) The angle of ... r) is given by sin i (C) Both (a) and (b) (D) Neither (a) nor (b)
Last Answer : Answer: Option B
Description : The angle of incidence for a wave A. can be measured between the incident ray and the normal B. can be measured between the incident wave front and the boundary C. is equal to the angle of reflection D. all of the above
Last Answer : D. all of the above
Description : In Fraunhofer diffraction, the incident wave front should be ….. A. elliptical B. Plane C. Spherical D. Cylindrical
Last Answer : B. Plane
Description : For transmission line, the incident voltage Ei = 6V, and Er = 3V. Calculate: (1) Reflection coefficient (2) Standing wave ratio
Last Answer : (1)Reflection coefficient (2) Standing wave ratio (1)Reflection coefficient Reflection coefficient R=Er/Ei =3/6 R=0.5 (2) Standing wave ratio SWR=Ei+Er/Ei-Er =6+3/6-3 SWR =3
Description : A light wave is incident over a plane surface with velocity x. After reflection the velocity becomes :
Last Answer : x
Last Answer : Whenever a wave is incident on a perfect conductor then the reflection coefficient is 0.