UPSC Essentials | Daily subject-wise quiz : Science and Technology MCQs on Pralay missile, SARs used in NISAR and more (Week 121)

QUESTION 1

With reference to the Pralay missile, consider the following statements:

1. It is an indigenously developed solid propellant quasi-ballistic missile.

2. This missile is capable of carrying multiple types of warheads against various targets.

3. The first test of Pralay was conducted in 2024.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— The Defence Research and Development Organisation (DRDO) conducted two consecutive successful tests of quasi-ballistic missile Pralay from Dr APJ Abdul Kalam island off the coast of Odisha

— The flight tests were carried out as a part of user evaluation trials to validate the maximum and minimum range capability of the missile system. “The missiles precisely followed the intended trajectory and reached the target point with pin-point accuracy meeting all the test objectives.

— Pralay is an indigenously-developed solid propellant quasi-ballistic missile employing state-of-the-art guidance and navigation to ensure high precision. The missile is capable of carrying multiple types of warheads against various targets. Hence, statements 1 and 2 are correct.

— The first test of Pralay (which means widespread destruction) was conducted in December 2021. The missile is slated to be armed with a conventional warhead and will be inducted into the artillery of the Indian Army. Hence, statement 3 is not correct.

Therefore, option (b) is the correct answer.

QUESTION 2

With reference to the Synthetic Aperture Radars (SARs) used in NISAR (NASA-ISRO Synthetic Aperture Radar), consider the following statements:

1. Both the L-band and S-band radars can see through clouds, smoke, rain or fog, thus getting an unfiltered view of the Earth across all weathers and through day and night.

2. The S-band SAR uses higher wavelength microwaves, which can better penetrate tree cover or vegetation, and even sand or ice.

3. The L-band SAR has a shorter wavelength, is unable to go much deeper, but is good for capturing the larger features, such as crop fields or water bodies.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— NISAR (NASA-ISRO Synthetic Aperture Radar) uniqueness is the two SARs that it is fitted with. Radars.

— A number of SAR-equipped satellites are currently deployed in space. ISRO’s RISAT (Radar Imaging Satellites) family of satellites, recently renamed the EOS series, carry SAR. Some of ISRO’s other Earth observation satellites, such as Cartosat and Oceansat, do not use SAR.

— The power of NISAR is derived from two SARs, one in the L-band and the other in the S-band. They are meant to record complementary sets of photographs for the same region at the same time, resulting in a hitherto unattainable level of detail on Earth. Both L-band and S-band radars can see through clouds, smoke, rain, and fog, providing an unfiltered image of the Earth in all weather conditions and at any time of day or night. Hence, statement 1 is correct.

— The L-band SAR, which uses higher wavelength microwaves, can better penetrate tree cover or vegetation, and even sand or ice. It is, therefore, able to capture minute details of surface undulations, and can see through dense forest cover, for example, to map the ground below and measure tree trunk biomass, which is very useful for estimating carbon stock. Hence, statement 3 is not correct.

— The S-band SAR, which has a shorter wavelength, is unable to go much deeper, but is good for capturing the larger features, such as crop fields or water bodies. It can observe crops like soybean, corn, sugarcane and provide information on their different growth and maturity stages. This observation will especially focus on India. Hence, statement 2 is not correct.

Therefore, option (a) is the correct answer.

QUESTION 3

With reference to the pollutants and their sources, consider the following pairs:

1. PM 2.5 – Predominantly produced by vehicle emissions and thermal power plants.

2. Nitrogen dioxide – Produced primarily due to the burning of fossil fuels by vehicles, thermal power plants, and various industrial processes.

3. Soot – It comes from sources such as vehicle exhaust emissions and burning wood.

How many of the pairs given above are correctly matched?

(a) Only one pair

(b) Only two pairs

(c) All three pairs

(d) None of the above pairs

Explanation

— According to a new large-scale study conducted by Cambridge University researchers, long-term exposure to air pollution increases the risk of getting dementia. The analysis, published in The Lancet Planetary Health on Thursday (July 24), is the most comprehensive assessment of its kind, based on a systematic examination of 51 studies and data from more than 29 million people exposed to air pollution for at least one year.

— The current study is the most extensive of its type, and it discovered a positive and statistically significant link between three prevalent air contaminants and dementia.

— PM2.5: Predominantly produced by vehicle emissions and thermal power plants, PM2.5 is extremely fine particulate matter with a diameter of 2.5 micrometres or less. The study found that for every 10 micrograms per cubic metre (µg/m³) of long-term exposure to PM2.5, an individual’s relative risk of dementia would increase by 17% from the baseline. Hence, pair 1 is correct.

— NO2: Nitrogen dioxide is produced primarily due to the burning of fossil fuels by vehicles, thermal power plants, and various industrial processes. The study found that for every 10 μg/m³ of long-term exposure to nitrogen dioxide, the relative risk of dementia increased by 3%. Hence, pair 2 is correct.

— Soot: Soot or Black Carbon PM2.5 comes from sources such as vehicle exhaust emissions and burning wood. The study reported that dementia risk jumped by 13% for each 1 μg/m³ of long-term soot exposure. The Central Pollution Control Board does not separately report BC/PM2.5 levels. Hence, pair 3 is correct.

Therefore, option (c) is the correct answer.

QUESTION 4

The term “hypocenter” with reference to an earthquake refers to:

(a) the location below the Earth’s surface where the earthquake starts

(b) the location on the surface of the Earth where it cracks

(c) the location from where the seismograph measures the intensity of the earthquake

(d) the location adjacent to the seismically prone region

Explanation

— A powerful magnitude 8.8 earthquake off Russia’s Far Eastern Kamchatka Peninsula triggered tsunami waves of up to 16 feet, which had started to American shores along Hawaii’s islands and off the coast of northern California.

— An earthquake is an intense shaking of the ground caused by movement under the Earth’s surface. It happens when two blocks of the Earth suddenly slip past one another. This releases stored-up ‘elastic strain’ energy in the form of seismic waves, which spread through the Earth and cause the shaking of the ground.

— The Earth’s outermost surface, crust, is fragmented into tectonic plates. The edges of the plates are called plate boundaries, which are made up of faults — zones of fractures between two blocks of rock. The tectonic plates constantly move at a slow pace, sliding past one another and bumping into each other. As the edges of the plates are quite rough, they get stuck with one another while the rest of the plate keeps moving.

— Earthquake occurs when the plate has moved far enough and the edges unstick on one of the faults. The United States Geological Survey (USGS) says that “the location below the Earth’s surface where the earthquake starts is called the hypocenter, and the location directly above it on the surface of the Earth is called the epicentre.”

Therefore, option (a) is the correct answer.

QUESTION 5

With reference to ‘ham’ radio, consider the following statements:

1. It is used for educational and knowledge purposes.

2. Communication can be set up between two licensed hams.

3. In India, individuals below the age of 21 are not permitted to operate a ham radio.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 only

(c) 2 and 3 only

(d) 1, 2 and 3

Explanation

— Shubhanshu Shukla, an Indian astronaut, used a ham radio from the International Space Station to communicate with schoolchildren in his home country.

— Amateur radio, sometimes known as ham radio, is a licensed radio service that uses radio waves to create communication. Ham radio service is mostly used for educational and informational purposes, as well as emergency or SOS communications. Trained ham operators can establish contact between two licensed amateur radio operators using a designated frequency, a transceiver, and an antenna. Hence, statements 1 and 2 are correct.

— Communication might be hyper-local, global, or space-based. In India, everyone over the age of 12 is entitled to use a ham radio. The Ministry of Electronics and Information Technology issues these licenses. Hence, statement 3 is not correct.

— In 1983, amateur radio was used for the first time on a space shuttle to communicate between space and Earth.

— The ISS also contains a ham radio, called the Amateur Radio on the International Space Station (ARISS), which is frequently used to coordinate astronaut-student contacts. The goal of such exchanges is to encourage the next generation.

— This teaching opportunity is supported by amateur radio organisations, as well as space agencies in the United States, Russia, Canada, Japan, and Europe, which provide equipment and operational support.

Therefore, option (a) is the correct answer.

QUESTION 6

With reference to the Indian Space Research Organisation (ISRO), consider the following statements:

1. It was established as a successor to INCOSPAR in 1969.

2. It is the nodal space agency under the Department of Space (DoS), which was formed in 1972.

3. Its core mandate includes designing launch vehicles, satellites, and applying space technology for societal development.

4. ISRO functions autonomously under the Ministry of Science & Technology.

Which of the statements given above are correct?

(a) 1 and 4 only

(b) 1, 2 and 3 only

(c) 2 and 4 only

(d) All of the above

Explanation

— Indian Space Research Organisation (ISRO) is the space agency of India. The organisation is involved in science, engineering and technology to harvest the benefits of outer space for India and the mankind.

— ISRO is a major constituent of the Department of Space (DOS), Government of India. The department executes the Indian Space Programme primarily through various Centres or units within ISRO.

— ISRO was previously the Indian National Committee for Space Research (INCOSPAR), set up by the Government of India in 1962, as envisioned by Dr. VikramA Sarabhai.

— ISRO was formed on August 15, 1969 and superseded INCOSPAR with an expanded role to harness space technology. DOS was set up and ISRO was brought under DOS in 1972.

— The prime objective of ISRO/DOS is the development and application of space technology for various national needs.

— ISRO has developed satellite launch vehicles, PSLV and GSLV, to place the satellites in the required orbits.

Therefore, option (b) is the correct answer.

(Other source: isro.gov.in)

QUESTION 7

What are Population III stars? 

(a) the first stars in the universe

(b) the recent stars in the universe.

(c) the smallest, long-living, dim stars.

(d) None of the above

Explanation

— The very first stars — so-called Population III stars — were unlike any we see today. Born from pristine hydrogen and helium, they were massive, short-lived, and intensely bright. Some may have been hundreds of times the mass of our Sun, burning hot and dying young in titanic supernovae that scattered heavy elements across space. These explosions seeded the universe with the ingredients for future generations of stars, planets, and eventually, life.

Therefore, option (a) is the correct answer.

QUESTION 8

With reference to ‘reionization’, consider the following statements:

1. It is an important phenomenon in our universe’s history as it presents one of the few means by which we can (indirectly) study these earliest stars. 

2. Scientists have recently discovered when the first stars were formed and when the reionization process started to occur.

Which of the above given statements is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Explanation

According to science.nasa.gov,

“The energetic ultraviolet light from these first stars was capable of splitting hydrogen atoms back into electrons and protons (or ionizing them). This era, from the end of the dark ages to when the universe was around a billion years old, is known as “the epoch of reionization.” It refers to the point when most of the neutral hydrogen was reionized by the increasing radiation from the first massive stars. Reionization is an important phenomenon in our universe’s history as it presents one of the few means by which we can (indirectly) study these earliest stars. But scientists do not know exactly when the first stars formed and when this reionization process started to occur.”

Therefore, option (a) is the correct answer.

Previous Daily Subject-Wise-Quiz

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 119)

Daily subject-wise quiz — Polity and Governance (Week 121)

Daily subject-wise quiz —  Science and Technology (Week 120)

Daily subject-wise quiz — Economy (Week 120)

Daily subject-wise quiz — Environment and Geography (Week 120)

Daily subject-wise quiz – International Relations (Week 120)

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