Science and Technology — UPSC Prelims Previous Year Questions

All 120 UPSC Prelims Science and Technology questions asked across 10 exam years, each with the correct answer, a detailed explanation and the source it was drawn from.

Science and Technology questions from UPSC Prelims 2025

Q1UPSC Prelims 2025Science and Technology

In the context of electric vehicle batteries, consider the following elements:

I. Cobalt
II. Graphite
III. Lithium
IV. Nickel

How many of the above usually make up battery cathodes?

  • (a)Only one
  • (b)Only two
  • (c)Only three
  • (d)All the four
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Q2UPSC Prelims 2025Science and Technology

Consider the following pairs:

Plant – Description
I. Cassava : Woody shrub
II. Ginger : Herb with pseudostem
III. Malabar spinach : Herbaceous climber
IV. Mint : Annual shrub
V. Papaya : Woody shrub

How many of the above pairs are correctly matched?

  • (a)Only two
  • (b)Only three
  • (c)Only four
  • (d)All the five
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Q3UPSC Prelims 2025Science and Technology

With reference to India's defence, consider the following pairs:

Aircraft type – Description
I. Dornier-228 : Maritime patrol aircraft
II. IL-76 : Supersonic combat aircraft
III. C-17 Globemaster III : Military transport aircraft

How many of the pairs given above are correctly matched?

  • (a)Only one
  • (b)Only two
  • (c)All the three
  • (d)None
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Q4UPSC Prelims 2025Science and Technology

Consider the following space missions:

I. Axiom-4
II. SpaDeX
III. Gaganyaan

How many of the space missions given above encourage and support micro-gravity research?

  • (a)Only one
  • (b)Only two
  • (c)All the three
  • (d)None
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Q5UPSC Prelims 2025Science and Technology

Consider the following statements:

Statement I:
Some rare earth elements are used in the manufacture of flat television screens and computer monitors.

Statement II:
Some rare earth elements have phosphorescent properties.

Which one of the following is correct in respect of the above statements?

  • (a)Both Statement I and Statement II are correct and Statement II explains Statement I
  • (b)Both Statement I and Statement II are correct but Statement II does not explain Statement I
  • (c)Statement I is correct but Statement II is not correct
  • (d)Statement I is not correct but Statement II is correct
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Q6UPSC Prelims 2025Science and Technology

With reference to monoclonal antibodies, often mentioned in news, consider the following statements:

I. They are man-made proteins.
II. They stimulate immunological function due to their ability to bind to specific antigens.
III. They are used in treating viral infections like that of Nipah virus.

Which of the statements given above are correct?

  • (a)I and II only
  • (b)II and III only
  • (c)I and III only
  • (d)I, II and III
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Q7UPSC Prelims 2025Science and Technology

Consider the following types of vehicles:

I. Full battery electric vehicles
II. Hydrogen fuel cell vehicles
III. Fuel cell electric hybrid vehicles

How many of the above are considered as alternative (powertrain) vehicles?

  • (a)Only one
  • (b)Only two
  • (c)All the three
  • (d)None
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Q8UPSC Prelims 2025Science and Technology

GPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation. Which of the following statements is/are correct in respect of GAGAN?

I. It is designed to provide additional accuracy and integrity.
II. It will allow more uniform and high quality air traffic management.
III. It will provide benefits only in aviation but not in other modes of transportation.

Select the correct answer using the code given below.

  • (a)I, II and III
  • (b)II and III only
  • (c)I only
  • (d)I and II only
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Q9UPSC Prelims 2025Science and Technology

With reference to Unmanned Aerial Vehicles (UAVs), consider the following statements:

I. All types of UAVs can do vertical landing.
II. All types of UAVs can do automated hovering.
III. All types of UAVs can use battery only as a source of power supply.

How many of the statements given above are correct?

  • (a)Only one
  • (b)Only two
  • (c)All the three
  • (d)None
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Q10UPSC Prelims 2025Science and Technology

Consider the following statements:

I. It is expected that Majorana 1 chip will enable quantum computing.
II. Majorana 1 chip has been introduced by Amazon Web Services (AWS).
III. Deep learning is a subset of machine learning.

Which of the statements given above are correct?

  • (a)I and II only
  • (b)II and III only
  • (c)I and III only
  • (d)I, II and III
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Q11UPSC Prelims 2025Science and Technology

Consider the following statements regarding AI Action Summit held in Grand Palais, Paris in February 2025:

I. Co-chaired with India, the event builds on the advances made at the Bletchley Park Summit held in 2023 and the Seoul Summit held in 2024.
II. Along with other countries, US and UK also signed the declaration on inclusive and sustainable AI.

Which of the statements given above is/are correct?

  • (a)I only
  • (b)II only
  • (c)Both I and II
  • (d)Neither I nor II
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Q12UPSC Prelims 2025Science and Technology

Consider the following statements:

I. No virus can survive in ocean waters.
II. No virus can infect bacteria.
III. No virus can change the cellular transcriptional activity in host cells.

Which of the statements given above are correct?

  • (a)Only one
  • (b)Only two
  • (c)All the three
  • (d)None
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Q13UPSC Prelims 2025Science and Technology

What is the common characteristic of the chemical substances generally known as CL-20, HMX and LLM-105, which are sometimes talked about in media?

  • (a)These are alternatives to hydro-fluorocarbon refrigerants
  • (b)These are explosives in military weapons
  • (c)These are high-energy fuels for cruise missiles
  • (d)These are fuels for rocket propulsion
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