JEE Main 2021 (Online) 16th March Evening Shift | Communication Systems Question 65 | Physics

Two identical antennas mounted on identical towers are separated from each other by a distance of 45 km. What should nearly be the minimum height of receiving antenna to receive the signals in line of sight? (Assume radius of earth is 6400 km)

158.2 m

79.1 m

19.77 m

39.55 m

JEE Main 2021 (Online) 16th March Morning Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

A 25 m long antenna is mounted on an antenna tower. The height of the antenna tower is 75 m. The wavelength (in meter) of the signal transmitted by this antenna would be :

200

400

100

300

JEE Main 2021 (Online) 25th February Evening Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

If a message signal of frequency 'f_m' is amplitude modulated with a carrier signal of frequency 'f_c' and radiated through an antenna, the wavelength of the corresponding signal in air is :

$${c \over {{f_c} + {f_m}}}$$

$${c \over {{f_c}}}$$

$${c \over {{f_c} - {f_m}}}$$

$${c \over {{f_m}}}$$

JEE Main 2021 (Online) 25th February Morning Shift

MCQ (Single Correct Answer)

-1

Out of Syllabus

Given below are two statements :

Statement I : A speech signal of 2 kHz is used to modulate a carrier signal of 1 MHz. The bandwidth requirement for the signal is 4 kHz.

Statement II : The side band frequencies are 1002 kHz and 998 kHz.

In the light of the above statements, choose the correct answer from the options given below :

Statement I is false but Statement II is true

Both Statement I and Statement II are false

Statement I is true but Statement II is false

Both Statement I and Statement II are true

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Questions Asked from Communication Systems (MCQ (Single Correct Answer))

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