UPSC Essentials | Daily subject-wise quiz : Science and Technology MCQs on flex-fuel vehicles, Astra’ missile and more (Week 170)

3. Flex-fuel vehicles use compression ignition similar to that of diesel engines.

4. Recently, India launched the world’s first vehicle powered entirely by ethanol.

Which one of the following conclusions based on the above statements is correct?

(a) There are four correct statements.

(b) There is only one correct statement.

(c) There are two correct statements, that include statement 3.

(d) There is no correct statement.

Relevance: Flex-fuel vehicles are important in the context of India’s Ethanol Blended Petrol (EBP) Programme, biofuels, and energy security. UPSC can ask conceptual questions on alternative fuels, vehicle technologies, and government initiatives for decarbonisation.

Explanation

—The government had originally planned to dispense petrol blended with 20% ethanol only by 2030, but the E20 fuel is now the standard petrol variant available nationwide. Since then, there has been a move to shift to E25 as the base fuel, with a simultaneous push for E85-100 fuels for specialised flex-fuel vehicles (FFVs).

—FFVs are essentially internal combustion engine vehicles engineered to operate on more than one type of fuel — typically petrol blended with ethanol or methanol. These vehicles use a fuel composition sensor to automatically adjust fuel injection and ignition timing based on the blend in the tank, allowing seamless switching between petrol and ethanol and varying degrees of blends. Hence, statement 1 is correct and statement 3 is not correct.

—FFVs emit greenhouse gases during combustion. Hence, statement 2 is not correct.

—It was way back in 1979 that Italian auto major Fiat launched the 147, the world’s first vehicle powered entirely by ethanol in Brazil. Hence, statement 4 is not correct.

Therefore, option (b) is the correct answer.

QUESTION 2

Consider the following statements about Alzheimer’s disease:

1. It is a disorder that slowly destroys a person’s memory and thinking skills.

2. The hippocampus is one of the first brain regions affected by Alzheimer’s disease.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Relevance: UPSC may ask conceptual questions on human physiology, brain anatomy, and disease mechanisms under Science and Technology.

Explanation

—People whose jobs require constant navigation, such as taxi and ambulance drivers, may have a lower risk of dying from Alzheimer’s disease, according to a large study that examined hundreds of occupations. The study, published in the British Medical Journal (BMJ), was led by researchers at Harvard University, who examined the employment histories and causes of death of millions of people in the United States.

—Alzheimer’s disease is the most common form of dementia, a brain disorder that slowly destroys a person’s memory and thinking skills. Hence, statement 1 is correct.

—One possible explanation is that these professions require workers to constantly plan routes, remember streets, adapt to changing traffic conditions, and navigate unfamiliar locations. In contrast, bus drivers, who typically follow fixed routes, did not show the same apparent protection.

—Scientists say the findings align with previous research showing that navigation skills influence the hippocampus, an essential part of the brain for memory and spatial awareness. The hippocampus is also one of the first brain regions affected by Alzheimer’s disease. Hence, statement 2 is correct.

Therefore, option (c) is the correct answer.

QUESTION 3

With reference to the ‘Neil Gehrels Swift Observatory’, consider the following statements:

1. It was designed to study gamma-ray bursts and other high-energy cosmic events.

2. An increase in solar activity has intensified atmospheric drag in low Earth orbit, causing Swift’s orbit to gradually decay.

3. It was designed with propulsion systems capable of raising its own orbit.

Which of the statements given above is/are correct?

(a) 1 only

(b) 1 and 2 only

(c) 2 and 3 only

(d) 2 only

Relevance: UPSC can ask conceptual questions on satellite orbits, space missions, electromagnetic radiation, and space agencies. The topic also links astronomy with space weather and its impact on satellite operations.

Explanation

—Nasa has successfully launched a first-of-its-kind rescue mission aimed at extending the life of one of its longest-serving space observatories. The mission sent a privately built spacecraft into orbit to rendezvous with the ageing Neil Gehrels Swift Observatory, which is gradually losing altitude and faces eventual destruction as atmospheric drag pulls it back toward Earth.

—The Swift Boost mission lifted off on Friday (July 3) at 4.36 am EDT (2.06 pm IST), with the LINK servicing spacecraft developed by Arizona-based Katalyst Space Technologies. Instead of launching from a conventional pad, the Pegasus XL rocket was released mid-air from Northrop Grumman’s L-1011 Stargazer aircraft over the Marshall Islands before igniting its engines and carrying LINK into orbit.

—Launched in November 2004, the Swift Observatory was designed to study gamma-ray bursts and other high-energy cosmic events. More than 20 years later, the telescope continues to deliver valuable scientific observations. Hence, statement 1 is correct.

—However, increased solar activity has intensified atmospheric drag in low Earth orbit, causing Swift’s orbit to gradually decay. Unlike many newer spacecraft, Swift was not designed with propulsion systems capable of raising its own orbit, leaving it vulnerable to eventual re-entry. Hence, statement 2 is correct and statement 3 is not correct.

Therefore, option (b) is the correct answer.

QUESTION 4

With reference to the ‘Astra’ missile, consider the following statements:

1. These are Beyond-visual-range (BVR) missiles.

2. Astra Mk 1 has a range of 80 to 110 km.

3. The missile lacks mid-course update.

4. At present, the missile is being integrated with the IAF’s Sukhoi-30 MKI fleet.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) Only three

(d) All four

Relevance: Indigenous defence systems such as Astra are important under the Defence Technology portion of Science and Technology. The topic is also relevant in the context of India’s defence indigenisation and Atmanirbhar Bharat initiatives.

Explanation

—India and Indonesia reached a significant milestone in their growing strategic cooperation by signing a deal for the supply of the Astra Mk 1 ‘beyond-visual-range air-to-air missiles’ (BVRAAM).

—Developed by the Defence Research and Development Organisation (DRDO), Astra is a family of indigenous BVRAAMs that will be integrated with the Air Force and the Navy. Beyond-visual-range (BVR) missiles are those capable of engaging beyond the range of 20 nautical miles, or 37 km. Air-to-air missiles are primarily fired from an airborne asset to destroy an airborne target. Hence, statement 1 is correct.

—The first in the family, Astra Mk 1, has a range of 80 to 110 km, an altitude of up to 20 km and a speed of Mach 4.5 (or 4.5 times the speed of sound). The key features of this missile include inertial guidance, mid-course update and terminal active radar homing. Hence, statement 2 is correct and statement 3 is not correct.

—The missile is being integrated with the IAF’s Sukhoi-30 MKI fleet and is also planned to be integrated with the indigenous Light Combat Aircraft Tejas Mk 1 A and the French Rafale jets in future. Hence, statement 4 is correct.

—A more advanced version of the Astra Mk 1 — the Astra Mk 2 — has an enhanced range of 200 km, from the earlier decided range of around 160 km.

Therefore, option (c) is the correct answer.

QUESTION 5

With reference to the Hayabusa 2 spacecraft, consider the following statements:

1. It was developed by the National Aeronautics and Space Administration.

2. It was launched in 2014 and became one of the world’s most successful asteroid missions after collecting samples from the asteroid Ryugu and returning them safely to Earth.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Relevance: Asteroid sample-return missions such as Hayabusa2, OSIRIS-REx, and India’s planned space missions are important current affairs topics for Science and Technology. The topic can also be linked with asteroid composition, Solar System evolution, and international space collaboration.

Explanation

—Japan’s Hayabusa2 spacecraft is preparing for one of the closest asteroid flybys ever attempted by a mission of its kind, with a high-speed encounter scheduled for July 5. The mission will bring the veteran spacecraft within as little as 1 km of the near-Earth asteroid Torifune, offering scientists a rare opportunity to study a largely unknown space rock while testing technologies that could aid future planetary defence missions.

—Hayabusa2, developed by the Japan Aerospace Exploration Agency (JAXA), was launched in 2014 and became one of the world’s most successful asteroid missions after collecting samples from the asteroid Ryugu and returning them safely to Earth in 2020. Although its primary mission ended with the successful sample return, the spacecraft remains operational and is now undertaking an ambitious extended mission. Hence, statement 1 is not correct and statement 2 is correct.

Therefore, option (b) is the correct answer.

Previous Daily Subject-Wise-Quiz

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 159)

Daily subject-wise quiz — Polity and Governance (Week 169)

Daily subject-wise quiz — Science and Technology (Week 169)

Daily subject-wise quiz — Economy (Week 169)

Daily subject-wise quiz — Environment and Geography (Week 169)

Daily subject-wise quiz – International Relations (Week 169)

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