WBCS Mains Applied Physics, Communication & Earth Science Questions 2023

Q. A television (TV) transmission is an example of which type of transmission?

(A) Simplex
(B) Half-duplex
(C) Full-duplex
(D) Bidirectional

Correct Answer: (A) Simplex

Q. The temperature of the Sun compared to the Earth is more than ______ K.

(A) 1000
(B) 500
(C) 5000
(D) 1,00,000

Correct Answer: (C) 5000

Q. Which type of modulation is employed in India for radio transmission?

(A) Amplitude modulation
(B) Frequency modulation
(C) Pulse modulation
(D) Phase modulation

Correct Answer: (A) Amplitude modulation

Q. The coldest layer of the atmosphere is

(A) Troposphere
(B) Stratosphere
(C) Mesosphere
(D) Thermosphere

Correct Answer: (C) Mesosphere

Q. ISRO launched sounding rockets for atmospheric studies. What is the name of the rocket?

(A) Car to Sat
(B) Agni-IV
(C) RH 300
(D) Brahmos-II

Correct Answer: (C) RH 300

Q. The main objective(s) of an industrial robot is to

(A) Minimize the labour requirement
(B) Increase productivity
(C) Enhance the life of production machines
(D) All of the above

Correct Answer: (D) All of the above

Q. Which of the following layers is also called the hot layer of the atmosphere?

(A) Troposphere
(B) Stratosphere
(C) Mesosphere
(D) Thermosphere

Correct Answer: (D) Thermosphere

Q. The downlink frequency in the C-band transponder is

(A) 2 GHz
(B) 4 GHz
(C) 14 GHz
(D) 11 GHz

Correct Answer: (B) 4 GHz

Q. The first geostationary satellite launched in 1964 was called

(A) ANIK
(B) SYNCOM-3
(C) WESTAR
(D) MOLNIYA

Correct Answer: (B) SYNCOM-3

Q. Pressure within the lungs is called

(A) Inter-pulmonary pressure
(B) Intra-pulmonary pressure
(C) Interstitial pressure
(D) Alveolar pressure

Correct Answer: (B) Intra-pulmonary pressure

Applied Physics, Communication & Earth Science Questions 2022

Q. ‘RADAR’ stands for:

(A) Radio Detection and Ranging
(B) Ready Advanced Appliance for Ranging
(C) Range Detection Appliance for Airplane Ranging
(D) Ready Advanced Airplane Ranging

Correct Answer: (A) Radio Detection and Ranging

Applied Physics, Communication & Earth Science Questions 2019

Q. What is the wavelength range of Super High Frequency (SHF), especially used in radar and satellite communication?

(A) 1 m – 10 m
(B) 1 cm – 10 cm
(C) 10 cm – 1 m
(D) 0.1 cm – 1 cm

Correct Answer: (B) 1 cm – 10 cm

Q. In TV transmission, the picture signal is ______ modulated.

(A) DSB-SC
(B) VSB
(C) SSB-SC
(D) Pulse

Correct Answer: (B) VSB

Q. The solar sunspot cycle is

(A) 3 years
(B) 7 years
(C) 11 years
(D) 14 years

Correct Answer: (C) 11 years

Applied Physics, Communication & Earth Science Questions 2017

Q. For television broadcasting, the frequency range employed normally varies from

(A) 30–300 MHz
(B) 30–300 GHz
(C) 30–300 kHz
(D) 30–300 Hz

Correct Answer: (A) 30–300 MHz

Q. Modern communication systems are based on

(A) Analog circuits
(B) Digital circuits
(C) Combination of analog and digital circuits
(D) None of the above

Correct Answer: (C) Combination of analog and digital circuits

Q. The technique used to transmit audio signals in television broadcasting is

(A) Amplitude modulation
(B) Frequency modulation
(C) Pulse code modulation
(D) Time division multiplexing

Correct Answer: (B) Frequency modulation

Applied Physics, Communication & Earth Science Questions 2016

Q. The frequency band used for radar relay systems and television is

(A) VLF
(B) UHF
(C) VHF
(D) EHF

Correct Answer: (B) UHF

Q. Which of the following satellites is used in ship-to-shore and shore-to-ship communication?

(A) Marisat
(B) Comsat
(C) Telstar
(D) Intelsat

Correct Answer: (A) Marisat

Q. Long-distance shortwave radio broadcasting uses

(A) Direct wave
(B) Sky wave
(C) Ionospheric wave
(D) Ground wave

Correct Answer: (B) Sky wave

Q. Intelsat satellite is used for

(A) Radar communication
(B) Radio communication
(C) Intercontinental communication
(D) None of the above

Correct Answer: (C) Intercontinental communication

Q. Which of the following electromagnetic waves is used by Bluetooth to exchange data over short distances?

(A) Microwaves
(B) Radio waves
(C) X-rays
(D) UV rays

Correct Answer: (A) Microwaves

Q. What frequency range of electromagnetic waves is used for commercial FM radio?

(A) 88 MHz to 108 MHz
(B) 88 GHz to 108 GHz
(C) 88 kHz to 108 kHz
(D) None of the above

Correct Answer: (A) 88 MHz to 108 MHz

Q. Red shift is an illustration of

(A) High-frequency absorption
(B) Low-temperature emission
(C) Doppler effect
(D) Unknown phenomenon

Correct Answer: (C) Doppler effect

Applied Physics, Communication & Earth Science Questions 2015

Q. The jet aircrafts fly very easily and smoothly in the lower stratosphere. What could be the appropriate explanation?

1. There are no clouds or water vapour in the lower stratosphere.
2. There are no vertical winds in the lower stratosphere.

(A) Only 1
(B) Only 2
(C) Both 1 and 2
(D) Neither 1 nor 2

Correct Answer: (C) Both 1 and 2