Prelims · Science & technology · 56 questions

IT, computing & emerging technologies

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Prelims 2023 · Q54

Easy

Consider the following actions:

1.Detection of car crash/collision which results in the deployment of airbags almost instantaneously
2.Detection of accidental free fall of a laptop towards the ground which results in the immediate turning off of the hard drive
3.Detection of the tilt of the smartphone which results in the rotation of display between portrait and landscape mode

In how many of the above actions is the function of accelerometer required?

Answer & explanation

Answer: (c) All three

All three actions need an accelerometer. An accelerometer is a sensor that measures changes in motion, and a crash, a free fall and a tilt each show up as a change in acceleration that the device can read.

✓ 1. Airbag systems decide whether to deploy from how abruptly the car's speed changes, which an accelerometer measures.
✓ 2. Drives in laptops use an accelerometer to sense free fall; the drive then parks its read-write head or powers down before impact to avoid damage.
✓ 3. A phone's accelerometer senses the direction of gravity, so it knows how the phone is tilted and rotates the display between portrait and landscape.

Remember · An accelerometer senses changes in motion. It triggers airbags, protects laptop drives in free fall and rotates phone screens.

Sources

New Accelerometer Calibration Service to Start Soon (National Institute of Standards and Technology, US) ↗ “Accelerometers, which detect changes in motion, are perhaps most familiar as the sensors that tell your mobile phone screen to rotate or determine whether automotive airbags should deploy based on how abruptly the car's speed changes.”
US Patent 7,369,345, Mobile hard disk drive free fall detection and protection (USPTO; text via Google Patents) ↗ · reference work “after a free fall event is detected, a signal is sent from the accelerometer to a processor to cause a signal to be sent to the voice coil motor to park the actuator arm.”

Question and answer: UPSC's official GS Paper I (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

Prelims 2023 · Q57

Easy

Which one of the following countries has its own Satellite Navigation System?

Answer & explanation

Answer: (d) Japan

Japan has its own satellite navigation system, the Quasi-Zenith Satellite System (QZSS, also called Michibiki). It is a regional system that works alongside GPS; the other three countries operate no navigation constellation of their own.

✓ (d) QZSS is Japan's own satellite positioning system, run by the Cabinet Office. The UN's navigation committee (ICG) lists Japan as a provider of a regional system, as it lists India for NavIC.
✗ (a) Australia takes part in the ICG only as a country with an active navigation-applications programme. It does not run a navigation constellation of its own.
✗ (b) Canada does not run its own navigation satellite system, and it is not listed among the ICG's system providers.
✗ (c) Israel does not run its own navigation satellite system, and it is not listed among the ICG's system providers.

Remember · Own navigation systems: USA (GPS), Russia (GLONASS), EU (Galileo), China (BeiDou), India (NavIC), Japan (QZSS). Australia, Canada and Israel have none.

Sources

Overview of the Quasi-Zenith Satellite System (QZSS), Cabinet Office, Government of Japan ↗ · reference work “QZSS is a Japanese satellite positioning system composed mainly of satellites in quasi-zenith orbits (QZO).”
ICG: Members (UN Office for Outer Space Affairs) ↗ · reference work “Japan (Michibiki Satellite-based Augmentation System (MSAS) and Quasi-Zenith Satellite Space Based Augmentation System (QZSS))”

Question and answer: UPSC's official GS Paper I (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

Prelims 2023 · Q72

Medium

With reference to Central Bank digital currencies, consider the following statements:

1.It is possible to make payments in a digital currency without using US dollar or SWIFT system.
2.A digital currency can be distributed with a condition programmed into it such as a time-frame for spending it.

Which of the statements given above is/are correct?

Answer & explanation

Answer: (c) Both 1 and 2

Both statements are correct. A central bank digital currency (CBDC) is the central bank's own money in digital form, so it can be moved directly between participants without a dollar leg or the SWIFT messaging network, and it can be programmed with rules such as an expiry date.

✓ 1. Multi-CBDC platforms such as the BIS-led Project mBridge let central banks and banks exchange their digital currencies peer to peer on a shared network, as an alternative to routing cross-border payments through correspondent banks and the dollar.
✓ 2. RBI's concept note on CBDC says money can be programmed by tying its end use, and that tokens may carry an expiry date by which they must be spent.

Remember · CBDC is sovereign money in digital form; it can settle cross-border payments directly between currencies and can be programmed, for example with an expiry date or a restricted use.

Sources

BIS press release: Project mBridge pilot on a cross-border CBDC platform (26 Oct 2022) ↗ “By enabling peer-to-peer and instant exchange of multiple CBDCs on a single network, Project mBridge aims to solve long-standing inefficiencies in cross-border payments”
RBI Concept Note on Central Bank Digital Currency (October 2022) ↗ “tokens may have an expiry date, by which they would need to be spent, thus ensuring consumption”

Question and answer: UPSC's official GS Paper I (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

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