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1.

Wave propagation in vacuum is lossy wave

a)

True

b)

False

2.

Wave propagation in free space in non dispersive wave

a)

True

b)

False

3.

When wave propagates in free space, the electric field vector is // to magnetic field vector

a)

true

b)

false

4.

When the wave propagates in free space, the electric field vector is // to propagation direction

a)

True

b)

False

5.

When the wave propagates in free space, the electric field vector and the magnetic field vector will in phase to each other

a)

True

b)

False

6.

E(t,x) = 40 exp(j6pi* 10^8 t) exp(j2pi*x)i_y. this wave is

a)

Transverse wave

b)

Travelling wave

c)

Reflective wave

d)

Standing wave

7.

E(t,z) = 40 exp ( j pi* 10^8 t) exp(j2pi*x)i_y. This wave is

a)

Forward wave

b)

Backward wave

c)

Standing wave

8.

E(t,z) = 40 exp(j6pi*10^8 t) exp(-j2pi*z)i_y. This wave is

a)

Lossy wave

b)

Non-lossy wave

c)

Backward wave

9.

E(t,z)= 40 exp(j6pi*1068)exp(-j2pi*z)i_y. Which one of these is right?

a)

E and H are not in phase

b)

E and H are in phase

c)

Lossy wave

d)

Dispersive wave

10.

E(t,z)= - 40 exp(j6pi*10^8 t) exp(-j2pi*z) i_y. The direction of electric field vector is

a)

+ x direction

b)

- y direction

c)

+ y direction

d)

- z direction

11.

E(t,z) = 10 exp(j6pi810^8) exp(-j2pi*z) i_y. the wave propagates in

a)

Medium

b)

Semiconductor

c)

Vacuum

12.

E(t,z) = 5 exp(j6pi* 10^8 t) exp(-j2pi*z)i_y. The propagation constant is

a)

3 pi (rad/m)

b)

pi ( rad/m)

c)

4 pi (rad/m)

d)

2 pi (rad/m)

13.

$E\left(t,z\right)\ =\ 5\ \exp\cdot\left(6\ \pi\times10^8t\right)\ \exp\left(-j\ 2\pi z\right)i_y$ . The frequency of the wave is

a)

3 Hz

b)

30 Hz

c)

300 MHz

d)

3 MHz

14.

$E\left(t,z\right)\ =\ 5\ \exp\cdot\left(j\ 6\pi\times10^{8\ \ }t\right)\ \exp\left(-\ j\ 2\ \pi j\right)i_y$ Wavelength is

a)

3 m

b)

10 m

c)

4 m

d)

1 m

15.

$E\left(t,z\right)\ =\ 5\ \exp\ \left(\ j\ 6\ \pi\times10^8t\right)\exp\left(\ -\ j\ 2\ \pi z\right)i_y$ The magnetic field vector direction is

a)

+ x direction

b)

- direction

c)

+ y direction

d)

- y direction.

16.

Time variable electromagnetic is caused by

a)

Alternative current

b)

Dielectric current

c)

Dielectric field

d)

Electric field

17.

Basic quantities of time variable electromagnetic will

a)

Change in time

b)

Change in space

c)

Unchange

18.

For time variable electromagnetic field, the electric field vector jusst changes with distance

a)

True

b)

False

19.

With time variable electromagnetic field

a)

dB/dz = 0

b)

dB/dz $\ne$ 0

c)

dE/dz = 0

20.

Magnetic field in vacuum is caused by time variable electric field vector

a)

True

b)

False

21.

A spatially magnetic field vector field produces an electric field

a)

True

b)

False

22.

Maxwell equation show relation between time variable electric field and time variable magnetic field

a)

true

b)

false

23.

Rot H = j . This means

a)

Field H is a closed field line

b)

Field H is an opened field line

c)

Field H has source

d)

Field H does not have source

24.

div B = 0. This means

a)

Field B has source

b)

Field B has no source

c)

Field B is a closed field

d)

Field B is an opened field.

25.

The principle of interchange is used to reduce the complexity of addressing the Maxwell equation

a)

True

b)

False

26.

Time variable electromagnetic field has energy

a)

True

b)

False

27.

Pointying vector has the same direction of magnetic field vector

a)

True

b)

False

28.

Ex x Pz = Hy

a)

true

b)

False

29.

An electromagnetic propagates in - y direction

a)

Ey= 0

b)

Hy = 0

c)

$Ey\ne0$

d)

$Hy\ \ne\ 0$

30.

For horizontal polarization wave

a)

E is perpendicular to incident wave

b)

E is parallel to incident wave

c)

E in linear with incident wave

31.

For vertical polarization wave

a)

E is perpendicular incident plane

b)

E is // incident wave

c)

E is in incident wave.

32.

$E1\ =10\ \cos\ \left(\ 2\ \pi\ x\ 10^6t\ -\ \pi z\right)i_x$ . Caculate E2 so that the total wave has an elliptical polarization

a)

$\ \$ $E_{2\ }=\ 20\ \cos\ \left(\ 2\ \pi\ 10^6\ t\ -\ \pi z\right)i_y$

b)

E2= $20\ \sin\left(2\pi\times10^6t\ -\pi z\right)i_y$

c)

$E2\ =\ 10\ \sin\left(2\pi10^6t\ -\pi z\right)i_y$

33.

$E1\ =10\ \cos\ \left(\ 2\ \pi\ x\ 10^6t\ -\ \pi z\right)i_x$ . Caculate E2 so that the total wave has a circular polarization

a)

$\ \$ $E_{2\ }=\ 20\ \cos\ \left(\ 2\ \pi\ 10^6\ t\ -\ \pi z\right)i_y$

b)

E2= $20\ \sin\left(2\pi\times10^6t\ -\pi z\right)i_y$

c)

$E2\ =\ 10\ \sin\left(2\pi10^6t\ -\pi z\right)i_y$

34.

$E1\ =10\ \cos\ \left(\ 2\ \pi\ x\ 10^6t\ -\ \pi z\right)i_x$ . Caculate E2 so that the total wave has a linear polarization

a)

$\ \$ $E_{2\ }=\ 20\ \cos\ \left(\ 2\ \pi\ 10^6\ t\ -\ \pi z\right)i_y$

b)

E2= $20\ \sin\left(2\pi\times10^6t\ -\pi z\right)i_y$

c)

$E2\ =\ 10\ \sin\left(2\pi10^6t\ -\pi z\right)i_y$

35.

$E1\ =10\ \cos\ \left(\ 2\ \pi\ x\ 10^6t\ -\ \pi z\right)i_x\ +\ 10\ \cos\ \left(\ 2\ \pi\ 10^{6\ }t\ -\ \pi z\ -\pi\ \right)$ . The polarization of the wave is

a)

Linear

b)

Elliptical

c)

Circular

36.

$H\ =\ \left(\left(1+\ 2i\ \right)i_y+\ \left(\ 2\ +\ 2i\right)i_z\right)\exp\left(-0.2x\right)\exp\left(-2ix\right).$ Polarization property of the wave is

a)

Linear

b)

Circular

c)

Elliptical

37.

In a good conductive medium, which parameters is not zero

a)

Phase coefficent

b)

Attuenation coefficent

c)

Both answers

38.

In a conductive medium

a)

Plane wave are dispersed

b)

Plane wave does not attenuate

c)

E and H are in phase

d)

Phase velocity does not change over frequency

39.

In a conductive medium, dielectric constant depends on frequency

a)

True

b)

False

40.

In a conductive medium, wave impedance is a real number

a)

True

b)

False

41.

In a good conductive medium, amplitude of E and H reduces dramatically over propagation distance

a)

True

b)

False

42.

In harmonic electric field we have the form $E\ =\ 10\ \exp\left(2\pi z\right)\exp\left(j6\pi x10^8t\right)\exp\left(j2\pi z\right)i_y$ . The property of transmitted wave is

a)

Amplitude = const over propagation distance

b)

E and H are out of phase

c)

Wave impedance is real number

43.

Skin effect only appears in

a)

Free space

b)

Vacuum

c)

Metal

44.

EM wave can propagate in super good conductive medium

a)

true

b)

false

45.

In a good conductive medium, attenuation coefficent and skin depth are the same

a)

True

b)

False

46.

Skin effect is a phenomenon that occurs in

a)

Conductive medium

b)

Semiconductor medium

c)

Dielectric medium

47.

Imaginary part of transmission const is

a)

Phase coefficent

b)

Attenuation coefficent

c)

Permiability

48.

Vector Poynting is

a)

Same direction of E

b)

Same direction of H

c)

Same direction of energy movement of electromagnetic field

49.

When wave propagates from free space to metal, wave propagates in free space is

a)

Travelling wave

b)

Standing wave

c)

TE wave

50.

Given the electric field in the form E= $10\ \exp\left(j\ 6\pi\ \cdot\ 10^8t\right)\exp\left(j2\Pi z\right)i_y$ . Properties of transmitted wave is

a)

Waves whose amplitudes does not vary with the direction

b)

Waves E and H are out of phase

c)

Wave disperse

51.

In ideal dielectric medium, E and H are out of phase

a)

True

b)

False

52.

In ideal dielectric medium, zero parameter is

a)

Loss

b)

Transmission

53.

$H\ =\ \left(\left(1+\ 2i\ \right)i_y+\ \left(\ 2\ +\ i\right)i_z\right)\exp\left(-0.2x\right)\exp\left(-2ix\right).$ Polarization property of the wave is

a)

Linear

b)

Circular

c)

Elliptical

54.

Magnetostatic caused by

a)

Shift current

b)

Alternating current

c)

Conductive current

55.

In a good conductive environment, the loss coefficent is much larger than phase coefficent

a)

True

b)

False

56.

When the wave travels to a good conductive medium, the higher the frequency of the wave, the

a)

The faster the wave attenuates

b)

The slower the wave attenuates

c)

The faster the wave travels

d)

The slower the wave travels

57.

For an electrostatic field, electric flux density depend on the medium

a)

True

b)

False

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Total questions: 57

Worksheet time: 29mins

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