(a) 1 only
(b) 1 and 2 only
(c) 2, 3 and 4
(d) 1, 2 and 3
Explanation
— Delhi’s much-anticipated cloud seeding experiment on October 28 failed to produce the desired rainfall, despite the hope that artificial showers could wash away the thick haze choking the city. While disappointment is understandable, this outcome should not come as a surprise. It reinforces what environmental scientists have long maintained: The capital’s pollution problem cannot be dispersed with one-off, high-visibility interventions.
— Cloud seeding is a weather modification technique that involves dispersing substances such as silver iodide or sodium chloride into clouds to encourage rainfall.
— It has been used in several countries, including China, the United States, and the UAE, mostly to tackle drought or enhance water availability. In India, it has been used intermittently in states such as Maharashtra and Karnataka for similar purposes.
Therefore, option (b) is the correct answer.
QUESTION 2
With reference to the CMS-03 satellite, consider the following statements:
1. It is a navigation satellite.
2. It will be launched to the Geosynchronous Transfer Orbit (GTO).
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
Explanation
— India’s LVM3 launch vehicle is scheduled to launch the CMS-03 communication satellite in its 5th operational flight (LVM3-M5) on November 02, 2025. Hence, statement 1 is not correct.
— CMS-03 is a multi-band communication satellite that will provide services over a wide oceanic region including the Indian landmass. CMS-03, weighing about 4400kg, will be the heaviest communication satellite to be launched to Geosynchronous Transfer Orbit (GTO) from Indian soil. Hence, statement 2 is correct.
— The previous mission of LVM3 launched the Chandrayaan-3 mission, where India became the first country to land successfully near the lunar south pole.
Therefore, option (b) is the correct answer.
(Source: www.isro.gov.in)
QUESTION 3
Consider the following statements about the Intrusion Detection System (IDS) for the protection of elephants
Statement 1: The Intrusion Detection System uses advanced optical fibre sensing technology to detect elephant movement near railway tracks.
Statement 2: When elephants come close to the railway tracks, the vibrations generated by their movement are detected by the sensor cables, which then transmit signals to the control room.
Which one of the following is correct in respect of the above statements?
(a) Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1.
(b) Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1.
(c) Statement 1 is correct but Statement 2 is incorrect.
(d) Statement 1 is incorrect but Statement 2 is correct.
Explanation
— To improve elephant safety and ensure smooth train operations, the Northeast Frontier Railway (NFR) has launched a major initiative across its network. The zone is implementing an Intrusion Detection System (IDS) designed to protect wildlife and maintain operational efficiency, especially in areas where railway lines pass through forested and elephant-inhabited zones.
— The Intrusion Detection System uses advanced optical fibre sensing technology to detect elephant movement near railway tracks, generating real-time alerts for train drivers and control rooms to take timely preventive action. Hence, statement 1 is correct.
— This means that when elephants come close to the railway tracks, the vibrations generated by their movement are detected by the sensor cables, which then transmit signals to the control room. Hence, statement 2 is correct.
Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1.
Therefore, option (a) is the correct answer.
QUESTION 4
Consider the following statements about Hoyle–Narlikar theory of gravity:
1. The Hoyle-Narlikar gravity theory proposed a “creation field” (C-field).
2. The Hoyle-Narlikar theory of gravity was widely accepted.
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
Explanation
— Mach’s principle, which states that every object’s mass is changed by its interaction with every other object, is central to the Hoyle-Narlikar gravity theory. The notion profoundly intrigued Einstein, but he was unable to incorporate it into his theories.
— The Hoyle-Narlikar gravity theory also proposed a “creation field” (C-field), which is a hypothetical negative-energy field that is responsible for the continual formation of matter. This helps to explain the steady-state cosmology, which holds that the universe has no beginning and would exist indefinitely. Hence, statement 1 is correct.
— The Hoyle-Narlikar theory of gravity was not widely accepted, particularly following the discovery of cosmic microwave background (CMB) radiation in 1965. The CMB, also known as an echo or shockwave of the Big Bang, is a cooled remnant of the first light to flow freely throughout the cosmos. Hence, statement 2 is not correct.
Therefore, option (a) is the correct answer.
QUESTION 5
The two scientific payloads, POLIX and XSPECT, are part of:
(a) ASTROSAT
(b) Chandrayaan-2
(c) Aditya-L1
(d) XPoSat
Explanation
— ISRO organised a National Meet on XPoSat mission and released the scientific data from the mission to the scientific community.
— XPoSat is India’s space-based X-Ray astronomy observatory in a Low Earth Orbit (LEO) of around 650 km altitude and 6 degrees of inclination. It carries two scientific payloads, viz. POLIX, aimed at measuring the degree and angle of polarization in medium X-ray energy range of 8-30 keV, and XSPECT, which will provide spectroscopic information in the energy range of 0.8-15 keV.
— The POLIX payload is developed by Raman Research Institute, Bengaluru in close coordination with ISRO, while the XSPECT payload is developed by U R Rao Satellite Centre (URSC), ISRO, Bengaluru.
Therefore, option (d) is the correct answer.
(Source: http://www.isro.gov.in)
Previous Daily Subject-Wise-Quiz
Daily Subject-wise quiz — History, Culture, and Social Issues (Week 128)
Daily subject-wise quiz — Polity and Governance (Week 134)
Daily subject-wise quiz — Science and Technology (Week 133)
Daily subject-wise quiz — Economy (Week 133)
Daily subject-wise quiz — Environment and Geography (Week 133)
Daily subject-wise quiz – International Relations (Week 133)
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DPYC said Delhi residents were promised rain for 15-20 minutes as relief from rising air pollution, but were misled by the government. Find a question on cloud seeding in today's quiz. (File) 
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