Prelims Power Play 2026 – Science Questions

1. With reference to the NISAR mission, consider the following statements:

• 1. It is an Earth observation satellite jointly developed by NASA and ISRO.
• 2. The satellite will be launched on the PSLV-C61 and put in a sun synchronous orbit.
• 3. The satellite will scan the entire globe every 30 days, providing a series of very detailed images of the Earth’s surface.
• 4. It will be the first satellite ever to observe the Earth in two frequencies.

How many of the statements given above are correct?

(a) Only one
(b) Only two
(c) Only three
(d) All four

Solution: Correct Answer: (a) Only one
Statement 1 is correct. Statement 2 is incorrect (GSLV Mark II). Statement 3 is incorrect (12-day cycle). Statement 4 is incorrect (specific dual-band SAR context).

2. With reference to the chromosphere, consider the following statements:

• 1. It is a region sandwiched between the sun’s atmosphere (the million-degree corona) and the photosphere (the sun’s visible surface).
• 2. It is in the chromosphere where the solar flares, hot plasma jets, and powerful energy fluxes originate.

Which of the statements given above are correct?

(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Solution: Correct Answer: (c) Both 1 and 2
The chromosphere is the dynamic transition layer of the Sun where significant energy events like flares and spicules occur.

3. Consider the following statements about MiG-21 fighter jets:

• 1. The Indian Air Force (IAF) is set to retire the remaining Russian origin MiG-21 fleet in a ceremonial decommissioning on September 19 at the Chandigarh airbase.
• 2. There are five squadrons of the MiG-21 Bisons currently active.

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

Solution: Correct Answer: (d) Neither 1 nor 2
The phase-out is targeted for 2025. Currently, active squadrons have been reduced to nearly one or two as they are replaced by LCA Tejas.

4. Which of the following viruses is also known as the ‘bleeding eye’ virus?

(a) Marburg virus
(b) Avian influenza
(c) Hepatitis B virus
(d) Hepatitis E virus

Solution: Correct Answer: (a) Marburg virus
Marburg virus causes severe hemorrhagic fever, often leading to bleeding from orifices, including the eyes.

5. Consider the following:

• 1. Sulphur compounds
• 2. Helium gas
• 3. Argon gas
• 4. Pyroclastic debris

How many of the following are byproducts of volcanic eruptions?

(a) Only one
(b) Only two
(c) Only three
(d) All four

Solution: Correct Answer: (d) All four
Volcanoes eject solid debris (pyroclastic) and a variety of gases including sulphur compounds and noble gases like Helium and Argon.

6. Consider the following statements regarding Europa (one of the moon of Jupiter):

Statement I: Europa, one of Jupiter’s moons, is considered a strong candidate in the search for extraterrestrial life.
Statement II: The James Webb Space Telescope has detected carbon dioxide and crystalline water ice on Europa’s surface, indicating recent exposure of subsurface ocean material.

(a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I
(b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I
(c) Statement-I is correct but Statement-II is incorrect
(d) Statement-I is incorrect but Statement-II is correct

Solution: Correct Answer: (a)
JWST's detection of carbon dioxide supports the theory of a habitable subsurface ocean, providing a scientific basis for life candidacy.

7. CoinDCX, recently in the news, is related to:

(a) A government digital payment initiative
(b) A space-tech startup collaborating with ISRO
(c) A cryptocurrency exchange that suffered a major hack
(d) A fintech app launched by RBI for rural banking

Solution: Correct Answer: (c)
CoinDCX is a major Indian crypto exchange frequently discussed in context of security and recent industry hacks.

8. With reference to the NASA’s sounding-rocket mission, consider the following statements:

• 1. The instrument SNIFS is designed to study the Sun’s chromosphere.
• 2. SNIFS will capture 3D spectroscopic data, obtaining a full spectrum for each pixel in view.
• 3. The mission will measure the hydrogen Lyman‑α spectral line.
• 4. SNIFS is an orbital satellite mission scheduled to operate for several years.

(a) 1 and 2 only
(b) 1, 2 and 3 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4

Solution: Correct Answer: (b) 1, 2 and 3 only
Statement 4 is incorrect because sounding rockets are sub-orbital, not orbital satellites.

9. 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.

(a) Only one
(b) Only two
(c) All three
(d) None

Solution: Correct Answer: (b) Only two
Statements 1 and 2 are correct. Statement 3 is incorrect; the first test was in 2021.

10. With reference to the Synthetic Aperture Radars (SARs) used in NISAR, consider the following statements:

• 1. Both the L-band and S-band radars can see through clouds, smoke, rain or fog.
• 2. The S-band SAR uses higher wavelength microwaves, which can better penetrate tree cover.
• 3. The L-band SAR has a shorter wavelength, is unable to go much deeper.

(a) Only one
(b) Only two
(c) All three
(d) None

Solution: Correct Answer: (a) Only one
Only statement 1 is correct. Statements 2 and 3 describe the L-band and S-band features in reverse (L-band has higher wavelength and deeper penetration).