A plane electromagnetic wave is propagating along the direction i ^ + j ^ 2 , with its polarization along the direction k . ^ The correct form of the magnetic field of the wave would be (here B 0 is an appropriate constant):

B 0 i ^ - j ^ 2 c o s ω t - k i ^ + j ^ 2

B 0 j ^ - i ^ 2 c o s ω t + k i ^ + j ^ 2

B 0 k ^ c o s ω t - k i ^ + j ^ 2

B 0 i ^ + j ^ 2 c o s ω t - k i ^ + j ^ 2

Match List – I with List – II . List – I List – II (a) 10 km height over earth's surface (i) Thermosphere (b) 70 km height over earth's surface (ii) Mesosphere (c) 180 km height over earth's surface (iii) Stratosphere (d) 270 km height over earth's surface (iv) Troposphere

( a )-( iv ), ( b )-( iii ), ( c )-( ii ), ( d )-( i )

( a )-( i ), ( b )-( iv ), ( c )-( iii ), ( d )-( ii )

( a )-( iii ), ( b )-( ii ), ( c )-( i ), ( d )-( iv )

( a )-( ii ), ( b )-( i ), ( c )-( iv ), ( d )-( iii )

EASY

Earn 100

What are the factors that cause attenuation in ground wave?

Important Questions on Space Communication

EASY

Physics>Modern Physics>Space Communication>Space Communication

The frequency suitable for beyond-the-horizon communication using sky waves is

EASY

Physics>Modern Physics>Space Communication>Space Communication

The physical sizes of the transmitter and receiver antenna in a communication system are:

EASY

Physics>Modern Physics>Space Communication>Space Communication

For television broadcasting the frequency employed is normally in range,

MEDIUM

Physics>Modern Physics>Space Communication>Space Communication

Which mode of propagation uses ionosphere to reflect the transmitted signals from the Earth ? State other two modes of propagation.

EASY

Physics>Modern Physics>Space Communication>Space Communication

A plane electromagnetic wave of wavelength

λ

has an intensity

I

. It is propagating along the positive

Y -

direction. The allowed expressions for the electric and magnetic fields are given by:

EASY

Physics>Modern Physics>Space Communication>Space Communication

Which type of communication is employed in mobile phones?

MEDIUM

Physics>Modern Physics>Space Communication>Space Communication

A plane electromagnetic wave is propagating along the direction

\frac{\hat{i} + \hat{j}}{\sqrt{2}},

with its polarization along the direction

\hat{k .}

The correct form of the magnetic field of the wave would be (here

B_{0}

is an appropriate constant):

EASY

Physics>Modern Physics>Space Communication>Space Communication

Match List

- I

with List

- II .

	List $- I$		List $- II$
(a)	$10 km$ height over earth's surface	(i)	Thermosphere
(b)	$70 km$ height over earth's surface	(ii)	Mesosphere
(c)	$180 km$ height over earth's surface	(iii)	Stratosphere
(d)	$270 km$ height over earth's surface	(iv)	Troposphere

MEDIUM

Physics>Modern Physics>Space Communication>Space Communication

A transmitting antenna at the top of a tower has a height $32 m$ and the height of the receiving antenna is $50 m$ . What is the maximum distance between them for satisfactory communication in line of sight (LOS) mode?

EASY

Physics>Modern Physics>Space Communication>Space Communication

Long-range radio transmission is possible when the radio waves are reflected from the ionosphere. For this to happen the frequency of the radio waves must be in the range:

EASY

Physics>Modern Physics>Space Communication>Space Communication

An EM wave is propagating in a medium with a velocity