September 26-2024 Prelims Practice Questions (PPQs)

Correct

Explanation

Option (b) is correct

• Penta-Erythritol-Tetra-Nitrate (PETN) was allegedly used in missions against Hezbollah.
• PETN is a powerful explosive with a Relative Effectiveness Factor (REF) of 1.66, making it more effective than Trinitrotoluene (TNT).
• PETN is produced by nitration of pentaerythritol using a mixture of nitric and sulfuric acids, which involves a chemical reaction that incorporates nitro groups into the pentaerythritol compound.
• Due to its potential use in explosives, PETN can be detected using chemical sensors and X-ray machines, enabling security personnel to identify it during inspections.
• It is used in military operations and has been involved in terrorist attacks, such as the 1996 Khobar Towers bombing in Saudi Arabia.

Answer: (b) An explosive material used in military and terrorist operations; Difficulty Level: Easy

Correct

Explanation

Option (b) is correct

• BMI (Body Mass Index) might not be the best way to measure health risks anymore.
• Instead, the Body Roundness Index (BRI) is proving to be better at predicting health conditions. This change has led healthcare professionals to consider BRI as a possible replacement for BMI.
• It was developed by U.S. mathematician Diana Thomas in 2013.
• It measures body roundness to assess health risks more accurately than the Body Mass Index (BMI).
• It incorporates waist circumference and height to estimate body fat percentage.
• Scores range from 1 to 15. Scores above 6.9 or below 3.41 indicate higher health risks.
• BRI provides a visual, egg-shaped outline with a green zone indicating the healthy range.
• Why BRI is Gaining Importance?
  • Ethnic Variability: BMI was based on 19th-century European populations and is inadequate for certain ethnic groups. BRI accommodates differences in fat distribution across populations, especially Asians, who tend to accumulate more abdominal fat at lower BMIs.
  • Accuracy of Fat Distribution: BRI aligns with body fat percentage and visceral fat levels, providing a more accurate picture of health risks than BMI.
  • Limitations of BMI: BMI only measures weight relative to height and does not differentiate between muscle, fat, or water. It also does not show where fat is distributed in the body.
  • Visceral Fat Indication: BRI includes waist circumference, offering a better indication of visceral fat (fat around internal organs) associated with cardiovascular diseases and metabolic syndromes.

Answer: (b) It helps measure body fat distribution, especially visceral fat, associated with health risks.; Difficulty Level: Easy

Correct

Explanation

Statement 1 is incorrect but 2 is correct

• NDCs are not legally binding commitments under the Paris Agreement.
• Update Requirements: Every country must update their NDCs every five years with increasingly higher ambition based on each country’s capabilities and capacities.
• Pledges made within an NDC are considered voluntary, with countries facing no legal penalty if they fail to meet their goals. However, they are obligated under the Paris Agreement to monitor progress and report on any failures.
• Some countries like Britain and Chile have incorporated their NDCs into national law, making their climate commitments legally binding at the national level.

Answer: (b) 2 only; Difficulty Level: Easy

Correct

Explanation

Statement 1 is correct

• The Sun doesn’t rotate as a solid body like the Earth. Different parts of the Sun rotate at different speeds – a phenomenon called differential rotation.
• The equator of the Sun rotates faster (about 25 days) compared to the poles (around 35 days). This difference is because the Sun is made of plasma (charged particles) and not a solid body.

Statement 2 is incorrect

• The Calcium K spectral line is actually located in the ultraviolet (UV) part of the electromagnetic spectrum, not the visible light spectrum.
• It is used to study the chromospheric network and solar plages (bright regions on the Sun’s surface), which are areas of increased magnetic activity.
• It is not primarily used to study solar wind patterns, which are studied through other tools and observations.

Statement 3 is correct

• The Sun’s differential rotation is an essential part of the process that generates its magnetic field, known as the solar dynamo.
• This magnetic field goes through cycles, leading to changes in solar activity approximately every 11 years.
• This cycle results in the appearance and disappearance of sunspots, solar flares, and other magnetic phenomena.
• The interaction between differential rotation and the Sun’s magnetic field is what drives this process.

Answer: (a) 1 and 3 only; Difficulty Level: Medium

Correct

Explanation

Option (c) is incorrect

• Currently, there is no antiviral treatment or licensed vaccine against dengue in India. ICMR & Panacea Biotec initiated the First Phase 3 Clinical Trial in India with the indigenous dengue vaccine, DengiAll.
• Dengue vaccine development is complex due to the need to achieve good efficacy for all four serotypes.

Options (a), (b) and (d) are correct

• Dengue is a viral infection transmitted by the Aedes aegypti mosquito.
• Reasons for the Surge:
  • Climate Change
    • Warmer Temperatures: Increased mosquito breeding and longer transmission seasons.
    • Unpredictable Weather Patterns: Heavy rains and dry spells create ideal breeding conditions.
  • Urbanisation:
    • Population Density: High population density in urban areas facilitates faster spread.
    • Water stagnation: Improper water storage in urban areas provides breeding grounds for mosquitoes.
  • Inadequate Public Health Measures:
    • Surveillance and Reporting: Inconsistent reporting and lack of robust surveillance systems.
    • Healthcare Infrastructure: Overburdened healthcare systems struggle to manage outbreaks effectively.

Answer: (c) There is a licensed vaccine available in India for dengue prevention; Difficulty Level: Easy

Correct

Explanation

Option (d) is correct

• Paigah tombs of Hyderabad is also known as Maqhbara Shams al-Umara.
• They are the final resting places of the Paigah nobility.
• The tombs are a prime example of Indo-Saracenic architecture, blending Asaf Jah and Rajputani styles.
• Built of white marble, the tombs feature intricately designed interiors. The structures are decorated with stucco work, representing Mughal, Greek, Persian, Asaf Jahi, Rajasthani, and Deccani styles.
• The famous ‘Jali’ work adds to the tombs’ allure. Each tomb is uniquely designed with a distinct style.
• Stucco, a construction material made of aggregates, a binder, and water, is used as a decorative coating for walls and ceilings and a sculptural and artistic material in architecture.

Answer: (d) Hyderabad; Difficulty Level: Easy

Correct

Explanation

• Antimony is a semi-metal. In its elemental form, it is a silvery white, brittle, fusible, crystalline solid that exhibits poor electrical and heat conductivity properties and vaporises at low temperatures.

Statement 1 is incorrect

• Antimony is not an abundant element but is found in small quantities in over 100 mineral species.
• China produces 88% of the world’s antimony.

Statement 2 is correct

• Antimony is used in the electronics industry to make semiconductor devices, such as infrared detectors and diodes and in plastic production as a heat stabiliser in PVC.
• It is used in solar panels to improve the stability of the solar performance of the glass upon exposure to UV radiations.
• A lead-antimony alloy is used in batteries. Other uses of antimony alloys include type metal (in printing presses), bullets and cable sheathing.
• Antimony compounds are used to make flame-retardant materials, paints, enamels, glass & potter

Answer: (b) 2 only; Difficulty Level: Medium