McqMate

56

56.5k

501. |
## The power of the electromagnetic wave with electric and magnetic field intensities given by 12 and 15 respectively is |

A. | 180 |

B. | 90 |

C. | 45 |

D. | 120 |

Answer» B. 90 |

502. |
## The transmission coefficient is given by 0.65. Find the return loss of the wave. |

A. | 9.11 |

B. | 1.99 |

C. | 1.19 |

D. | 9.91 |

Answer» A. 9.11 |

503. |
## The intrinsic impedance of a wave with electric and magnetic field of 10 and 8 respectively is |

A. | 1.6 |

B. | 1.11 |

C. | 1.25 |

D. | 0.8 |

Answer» B. 1.11 |

504. |
## The intrinsic impedance in free space is |

A. | 60π |

B. | 12π |

C. | 6π |

D. | 120π |

Answer» D. 120π |

505. |
## The skin effect is a phenomenon observed in |

A. | insulators |

B. | dielectrics |

C. | conductors |

D. | semiconductors |

Answer» C. conductors |

506. |
## The skin depth is measured in |

A. | meter |

B. | millimetre |

C. | centimetre |

D. | micrometer |

Answer» D. micrometer |

507. |
## The attenuation constant is 0.5 units. The skin depth will be |

A. | 0.5 |

B. | 0.25 |

C. | 2 |

D. | 4 |

Answer» C. 2 |

508. |
## The relation between the skin depth and frequency is given by |

A. | skin depth α f |

B. | skin depth α 1/f |

C. | skin depth α √f |

D. | skin depth α 1/√f |

Answer» D. skin depth α 1/√f |

509. |
## The skin depth of the wave having a frequency of 3MHz and a velocity of 12 m/s is |

A. | 2 |

B. | 3 |

C. | 4 |

D. | 6 |

Answer» C. 4 |

510. |
## The coaxial cable consists of |

A. | conductors |

B. | dielectric |

C. | conductor with dielectric |

D. | two conductors with dielectric |

Answer» D. two conductors with dielectric |

511. |
## The transmission line is said to be lossless when the |

A. | conductor is perfect and dielectric is lossless |

B. | conductor is perfect and dielectric is lossy |

C. | conductor is imperfect and dielectric is lossy |

D. | conductor is imperfect and dielectric is lossless |

Answer» A. conductor is perfect and dielectric is lossless |

512. |
## The resistance of a lossless transmission line is |

A. | 0 |

B. | 1 |

C. | -1 |

D. | infinity |

Answer» A. 0 |

513. |
## The attenuation constant is measured in the units of |

A. | ohm |

B. | neper |

C. | decibel |

D. | radian/sec |

Answer» B. neper |

514. |
## The condition that holds good in a distortionless transmission line is |

A. | r/l = g/c |

B. | rl = gc |

C. | l/r = c/g |

D. | rg/lc |

Answer» A. r/l = g/c |

515. |
## Given that R = 20 ohm, L = 40 mH, C = 40 μF, G = 0.02 mho. Find whether the line is distortionless or not. |

A. | distorted line |

B. | distortionless line |

C. | all of the mentioned |

D. | none of the mentioned |

Answer» B. distortionless line |

516. |
## For R= 20 ohm and G= 0.8 mho, the attenuation constant will be |

A. | 16 |

B. | 4 |

C. | 2 |

D. | 32 |

Answer» A. 16 |

517. |
## The Smith chart is a polar chart which plots |

A. | r vs z |

B. | r vs znorm |

C. | t vs z |

D. | t vs znorm |

Answer» B. r vs znorm |

518. |
## The Smith chart consists of the |

A. | constant r and variable x circles |

B. | variable r and constant x circles |

C. | constant r and constant x circles |

D. | variable r and variable x circles |

Answer» C. constant r and constant x circles |

519. |
## The circles in the Smith chart pass through which point? |

A. | (0,1) |

B. | (0,-1) |

C. | (-1,0) |

D. | (1,0) |

Answer» D. (1,0) |

520. |
## Moving towards the clockwise direction in the Smith chart implies moving |

A. | towards generator |

B. | towards load |

C. | towards stub |

D. | towards waveguide |

Answer» A. towards generator |

521. |
## The centre of the point having a normalised resistance of 1.2 ohm and reactance of 1.5 ohm is |

A. | (0.54,0) |

B. | (0.45,0) |

C. | (0.36,0) |

D. | (0.78,0) |

Answer» A. (0.54,0) |

522. |
## The normalised load impedance of the transmission line 50 ohm with a load of 30 ohm is |

A. | 30 |

B. | 150 |

C. | 5/3 |

D. | 3/5 |

Answer» D. 3/5 |

523. |
## The radius of the point having a normalised resistance of 1 ohm is |

A. | 1 |

B. | 0.2 |

C. | 0.5 |

D. | 0.25 |

Answer» C. 0.5 |

524. |
## The open circuit line will have a reflection coefficient of |

A. | 0 |

B. | 1 |

C. | -1 |

D. | ∞ |

Answer» B. 1 |

525. |
## For time varying currents, the field or waves will be |

A. | electrostatic |

B. | magneto static |

C. | electromagnetic |

D. | electrical |

Answer» C. electromagnetic |

526. |
## According to Faraday’s law, EMF stands for |

A. | electromagnetic field |

B. | electromagnetic force |

C. | electromagnetic friction |

D. | electromotive force |

Answer» D. electromotive force |

527. |
## Find the displacement current when the flux density is given by t3 at 2 seconds. |

A. | 3 |

B. | 6 |

C. | 12 |

D. | 27 |

Answer» C. 12 |

528. |
## Find the force due to a current element of length 2cm and flux density of 12 tesla. The current through the element will be 5A. |

A. | 1 n |

B. | 1.2 n |

C. | 1.4 n |

D. | 1.6 n |

Answer» B. 1.2 n |

529. |
## When the conduction current density and displacement current density are same, the dissipation factor will be |

A. | zero |

B. | minimum |

C. | maximum |

D. | unity |

Answer» D. unity |

530. |
## The divergence of which quantity will be zero? |

A. | e |

B. | d |

C. | h |

D. | b |

Answer» D. b |

531. |
## 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 |

Answer» B. 9 |

532. |
## 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 |

Answer» C. curl(e) = -db/dt |

533. |
## Find the Maxwell law derived from Ampere law. |

A. | div(i) = h |

B. | div(h) = j |

C. | curl(h) = j |

D. | curl(b) = d |

Answer» C. curl(h) = j |

534. |
## In which of the following forms can Maxwell’s equation not be represented? |

A. | static |

B. | differential |

C. | integral |

D. | harmonic |

Answer» A. static |

535. |
## The charge build up in the capacitor is due to which quantity? |

A. | conduction current |

B. | displacement current |

C. | convection current |

D. | direct current |

Answer» B. displacement current |

536. |
## 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 |

Answer» A. curl(h) = j |

537. |
## Find the flux enclosed by a material of flux density 12 units in an area of 80cm. |

A. | 9.6 |

B. | 12/80 |

C. | 80/12 |

D. | 12/0.8 |

Answer» A. 9.6 |

538. |
## Find the electric flux density of a material with charge density 16 units in unit volume. |

A. | 1/16 |

B. | 16t |

C. | 16 |

D. | 162 |

Answer» C. 16 |

539. |
## Find the conductivity of a material with conduction current density 100 units and electric field of 4 units. |

A. | 25 |

B. | 400 |

C. | 0.04 |

D. | 1600 |

Answer» A. 25 |

540. |
## 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 |

Answer» B. 10cos 0.5t |

541. |
## The power of the electromagnetic wave with electric and magnetic field intensities given by 12 and 15 respectively is |

A. | 180 |

B. | 90 |

C. | 45 |

D. | 120 |

Answer» B. 90 |

542. |
## The power of a wave of with voltage of 140V and a characteristic impedance of 50 ohm is |

A. | 1.96 |

B. | 19.6 |

C. | 196 |

D. | 19600 |

Answer» C. 196 |

543. |
## The power reflected by a wave with incident power of 16 units is(Given that the reflection coefficient is 0.5) |

A. | 2 |

B. | 8 |

C. | 6 |

D. | 4 |

Answer» D. 4 |

544. |
## The incident and the reflected voltage are given by 15 and 5 respectively. The transmission coefficient is |

A. | 1/3 |

B. | 2/3 |

C. | 1 |

D. | 3 |

Answer» B. 2/3 |

545. |
## The current reflection coefficient is given by -0.75. Find the voltage reflection coefficient. |

A. | -0.75 |

B. | 0.25 |

C. | -0.25 |

D. | 0.75 |

Answer» D. 0.75 |

546. |
## The attenuation is given by 20 units. Find the power loss in decibels. |

A. | 13.01 |

B. | 26.02 |

C. | 52.04 |

D. | 104.08 |

Answer» A. 13.01 |

547. |
## The curl of the electric field intensity is |

A. | conservative |

B. | rotational |

C. | divergent |

D. | static |

Answer» B. rotational |

548. |
## Which of the following identities is always zero for static fields? |

A. | grad(curl v) |

B. | curl(div v) |

C. | div(grad v) |

D. | curl(grad v) |

Answer» D. curl(grad v) |

549. |
## 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 |

Answer» C. 5cos t |

550. |
## Find the magnetic field intensity when the magnetic vector potential x i + 2y j + 3z k. |

A. | 6 |

B. | -6 |

C. | 0 |

D. | 1 |

Answer» B. -6 |

551. |
## The value of ∫ H.dL will be |

A. | j |

B. | i |

C. | b |

D. | h |

Answer» B. i |

552. |
## Given the vector potential is 16 – 12sin y j. Find the field intensity at the origin. |

A. | 28 |

B. | 16 |

C. | 12 |

D. | 4 |

Answer» C. 12 |

553. |
## The Laplacian of the magnetic vector potential will be |

A. | –μ j |

B. | – μ i |

C. | –μ b |

D. | –μ h |

Answer» A. –μ j |

554. |
## Find the gradient of t = x2y+ ez at the point p(1,5,-2) |

A. | i + 10j + 0.135k |

B. | 10i + j + 0.135k |

C. | i + 0.135j + 10k |

D. | 10i + 0.135j + k |

Answer» B. 10i + j + 0.135k |

555. |
## + z2 at (1,1,1) |

A. | i + j + k |

B. | 2i + 2j + 2k |

C. | 2xi + 2yj + 2zk |

D. | 4xi + 2yj + 4zk |

Answer» B. 2i + 2j + 2k |

556. |
## i + 2xy j + 5xz2 k |

A. | √4.01 |

B. | √4.02 |

C. | √4.03 |

D. | √4.04 |

Answer» D. √4.04 |

557. |
## ,2,5) is (in Joule) |

A. | 0.64 |

B. | 0.72 |

C. | 0.78 |

D. | 0.80 |

Answer» B. 0.72 |

558. |
## /x) j + 5 k. |

A. | -8.014 |

B. | -8.114 |

C. | -8.214 |

D. | -8.314 |

Answer» C. -8.214 |

559. |
## πε) ln(b/a). State True/False. |

A. | true |

B. | false |

Answer» A. true |

560. |
## i in spherical coordinates with r = 4m and θ = π/2. |

A. | 600 |

B. | 599.8 |

C. | 588.9 |

D. | 577.8 |

Answer» C. 588.9 |

561. |
## and 1, y = 0 and 2, z = 0 and 3. |

A. | 10 |

B. | 12 |

C. | 14 |

D. | 16 |

Answer» B. 12 |

562. |
## in volume integral. |

A. | 80 π |

B. | 5 π |

C. | 75 π |

D. | 85 π |

Answer» C. 75 π |

563. |
## , hence find charge using volume integral. |

A. | 6100 π |

B. | 6200 π |

C. | 6300 π |

D. | 6400 π |

Answer» D. 6400 π |

564. |
## j. |

A. | 20 |

B. | 70/3 |

C. | 80/3 |

D. | 30 |

Answer» C. 80/3 |

565. |
## = 9. |

A. | 120π |

B. | 180π |

C. | 240π |

D. | 300π |

Answer» B. 180π |

566. |
## 5cm apart in transformer oil(εr=2.2) in 10-4 N, |

A. | 8.15 |

B. | 5.18 |

C. | 1.518 |

D. | 1.815 |

Answer» D. 1.815 |

567. |
## 5 X 10-7 C, both the charges are in vacuum. |

A. | 0.03 |

B. | 0.05 |

C. | 0.07 |

D. | 0.09 |

Answer» D. 0.09 |

568. |
## cm in vacuum(in 10-8C) |

A. | 4 |

B. | 2 |

C. | 8 |

D. | 6 |

Answer» A. 4 |

569. |
## cm and minimises as d increases. State True/False |

A. | true |

B. | false |

Answer» A. true |

570. |
## 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 |

Answer» A. true |

571. |
## ,1,1)m? |

A. | 10-6 |

B. | -10-6 |

C. | 106 |

D. | -106 |

Answer» B. -10-6 |

572. |
## 14 units? |

A. | 1 |

B. | 0.75 |

C. | 0.5 |

D. | 0.25 |

Answer» D. 0.25 |

573. |
## Find the potential of V = 60sin θ/r2 at P(3,60,25) |

A. | 5.774 |

B. | 6.774 |

C. | 7.774 |

D. | 8.774 |

Answer» A. 5.774 |

574. |
## ,1,3). |

A. | 105 |

B. | 106 |

C. | 107 |

D. | 108 |

Answer» B. 106 |

575. |
## What is the potential difference between 10sinθcosφ/r2 at A(1,30,20) and B(4,90,60)? |

A. | 2.386 |

B. | 3.386 |

C. | 4.386 |

D. | 5.386 |

Answer» C. 4.386 |

576. |
## m from the ring. |

A. | 18π |

B. | 24π |

C. | 36π |

D. | 72π |

Answer» D. 72π |

577. |
## at R = 4m and σ = -3 at R = 5m. Find the flux density at R = 1m. |

A. | 0 |

B. | 1 |

C. | 2 |

D. | 3 |

Answer» A. 0 |

578. |
## at R = 4m and σ = -3 at R = 5m. Find the flux density at R = 3m. |

A. | 3 |

B. | 10/3 |

C. | 11/3 |

D. | 4 |

Answer» B. 10/3 |

579. |
## at R = 4m and σ =-3 at R = 5m. Find the flux density at R = 4.5m. |

A. | 4/4.5 |

B. | 3/4.5 |

C. | 2/4.5 |

D. | 1/4.5 |

Answer» C. 2/4.5 |

580. |
## at R = 4m and σ = -3 at R = 5m. Find the flux density at R = 6m. |

A. | 17/6 |

B. | -17/6 |

C. | 13/6 |

D. | -13/6 |

Answer» D. -13/6 |

581. |
## Find the electric potential for an electric field 3units at a distance of 2m. |

A. | 9 |

B. | 4 |

C. | 6 |

D. | 3/2 |

Answer» C. 6 |

582. |
## -10 units) |

A. | 2.1 |

B. | 2.33 |

C. | 2.5 |

D. | 2.77 |

Answer» C. 2.5 |

583. |
## Transform the vector A = 3i – 2j – 4k at P(2,3,3) to cylindrical coordinates |

A. | -3.6j – 4k |

B. | -3.6j + 4k |

C. | 3.6j – 4k |

D. | 3.6j + 4k |

Answer» A. -3.6j – 4k |

584. |
## , -2) |

A. | 2.467i + j + 1.167k |

B. | 2.467i – j + 1.167k |

C. | 2.467i – j – 1.167k |

D. | 2.467i + j – 1.167k |

Answer» A. 2.467i + j + 1.167k |

585. |
## Transform the vector (4,-2,-4) at (1,2,3) into spherical coordinates. |

A. | 3.197i – 2.393j + 4.472k |

B. | -3.197i + 2.393j – 4.472k |

C. | 3.197i + 2.393j + 4.472k |

D. | -3.197i – 2.393j – 4.472k |

Answer» B. -3.197i + 2.393j – 4.472k |

586. |
## units. |

A. | 500 |

B. | 250 |

C. | 1000 |

D. | 2000 |

Answer» C. 1000 |

587. |
## m/s. |

A. | 16.67 |

B. | 2400 |

C. | 2880 |

D. | 0.06 |

Answer» B. 2400 |

588. |
## units. |

A. | 200 |

B. | 50 |

C. | 400 |

D. | 0.02 |

Answer» A. 200 |

589. |
## units and E = 8 units. |

A. | 1.77 |

B. | 2.25 |

C. | 36 |

D. | 144 |

Answer» C. 36 |

590. |
## units. |

A. | 3 |

B. | 2 |

C. | 60 |

D. | 2.4 |

Answer» C. 60 |

591. |
## 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 |

Answer» D. 1.73 |

592. |
## kV. |

A. | 350n |

B. | 0.035kn |

C. | 0.035n |

D. | 3.35kn |

Answer» C. 0.035n |

593. |
## kV. Find „a‟. |

A. | 1m |

B. | 1cm |

C. | 10cm |

D. | 1mm |

Answer» D. 1mm |

594. |
## kV. Find „a‟. |

A. | 10mm |

B. | 100mm |

C. | 1000m |

D. | 1000cm |

Answer» D. 1000cm |

595. |
## The unit for dielectric strength is ____________ |

A. | v/m2 |

B. | mv/m2 |

C. | mv/m |

D. | vm |

Answer» C. mv/m |

596. |
## m, calculate the dielectric strength. |

A. | 2mv/m |

B. | 4mv/m |

C. | 6mv/m |

D. | 8mv/m |

Answer» A. 2mv/m |

597. |
## Leakage in capacitors is primarily caused by _________ |

A. | transistors |

B. | resistors |

C. | inductors |

D. | dc motors |

Answer» A. transistors |

598. |
## The flow of electrons in dielectric is due to _________ |

A. | conduction |

B. | potential difference |

C. | breakdown |

D. | resistance |

Answer» C. breakdown |

599. |
## Displacement current depends on ___________ |

A. | moving charges |

B. | change in time |

C. | both moving charges and change in time |

D. | neither moving charges nor change in time |

Answer» B. change in time |

600. |
## Paper capacitor is a type of _________ |

A. | fixed capacitor |

B. | variable capacitor |

C. | either fixed or variable depending on its usage |

D. | neither fixed nor variable |

Answer» A. fixed capacitor |

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