Daily Quiz 25 April 2025

Answer: C

Explanation:

• Option C is correct: Central Bureau of Investigation launched Operation Chakra-V against Transnational Organized Cybercrime/ Digital Arrests.

Recently, the CBI has arrested four people, two each from Mumbai and Moradabad (Uttar Pradesh), for their alleged involvement in ‘Digital Arrests’ fraud. The arrests, made as part of ‘Operation Chakra V’, followed searches at 12 locations.

Answer: A

Explanation:

• Option A is correct: The mantis shrimp is a colourful, 10-cm-long resident of the ocean whose appearance belies its reputation as one of the most fearsome predators on the planet.
• These unassuming crustaceans use a hammer-shaped appendage called the dactyl club to strike their prey at a blistering 23 m/s (about 50-times faster than the blink of an eye), smashing into the poor creature’s body like a bullet from a gun fired point blank. The strike releases enough energy to send small shockwaves through the surrounding water.
• The dactyl club of a mantis shrimp stores its energy in spring-like elastic structures held together by latch-like tendons. When the latch is released, the club is released. As it moves to deliver its punch, it displaces the surrounding water and forms small low-pressure zones. Inside these zones, the water’s density drops so much that it turns into vapour, leaving behind a bubble.
• When these bubbles collapse due to the pressure of the surrounding water, they release a considerable amount of heat and shockwaves of very high frequencies, up to hundreds of megahertz. Thus, each dactyl-club punch delivers two blows: one from its own punch and the other from the collapsing bubbles, and together they are capable of breaking the tough shells of clams, mussels, and other crustaceans.
• The mantis shrimp delivers powerful punches using a dactyl club, but due to its unique internal microstructure that exhibits phononic shielding and hierarchical design, the recoil is dispersed effectively, preventing self-injury. This shielding blunts the flow of acoustic waves, making it an example of nature’s metamaterial.
• So, Both Statement-I and Statement-II are correct and Statement-II explains Statement-I.

Answer: B

Explanation:

• One of the key components of the National Rural Health Mission is to provide every village in the country with a trained female community health activist ASHA or Accredited Social Health Activist. Selected from the village itself and accountable to it, the ASHA will be trained to work as an interface between the community and the public health system. Following are the key components of ASHA :
  • Statement 1 is not correct: ASHA must primarily be a woman resident of the village married/ widowed/ divorced, preferably in the age group of 25 to 45 years.
  • Statement 2 is correct: She should be a literate woman with due preference in selection to those who are qualified up to 10 standard wherever they are interested and available in good numbers. This may be relaxed only if no suitable person with this qualification is available.
  • ASHA will be chosen through a rigorous process of selection involving various community groups, self-help groups, Anganwadi Institutions, the Block Nodal officer, District Nodal officer, the village Health Committee and the Gram Sabha.
  • Capacity building of ASHA is being seen as a continuous process. ASHA will have to undergo series of training episodes to acquire the necessary knowledge, skills and confidence for performing her spelled out roles.

Statement 3 is correct: The ASHAs will receive performance-based incentives for promoting universal immunization, referral and escort services for Reproductive & Child Health (RCH) and other healthcare programmes, and construction of household toilets.

Answer: D

Explanation:

• Option D is correct: In magnetic technology, rare-earth magnets are permanent magnets composed of alloys of rare-earth elements. A rare-earth magnet has a much higher performance than ceramic magnets and alnico magnets. Magnets of this type typically have a remanence exceeding 1.2 Tesla and are the strongest among permanent magnets. There are two types of rare earth magnets, varying in grades (strengths) and having different magnetic and physical properties:
  • Neodymium magnets (NdFeB): Neodymium is the most affordable and strongest output rare earth magnet. Applications of Rare Earth Neodymium
    • Magnetic separators
    • Actuators with linear motion
    • Microphones or Audio applications
    • DC motors (automotive starters)
    • Disk drives, printers, and speakers for computers
    • Devices for medical use
  • Samarium Cobalt magnets(SmCo): A Samarium Cobalt (SmCo) magnet also has strong magnetic properties. They are more prone to break or chip when dropped or snapped together. Therefore, they should be handled and packed carefully to prevent damage to the magnets. Applications of Rare Earth Samarium Cobalt
    • Tubes for travelling waves
    • Satellite systems and linear actuators
    • When temperature stability is crucial
    • Magnetic Couplings

Magnets for Sensors

Answer: C

Explanation:

• QNu Labs, one of the startups selected by the Department of Science and Technology (DST) under the National Quantum Mission (NQM), has launched world’s first and unique platform, QShield that enables seamless cryptography management across any environment — cloud, on-premises, or hybrid.
• Statement 1 is correct: QShield was launched by QNu Labs, a startup selected under the National Quantum Mission by the Department of Science and Technology.

Statement 2 is correct: The platform integrates multiple technologies including Quantum Key Distribution (Armos), Post-Quantum Cryptography, Quantum Random Number Generator (Tropos), and Quantum Hardware Security Module (QHSM) to provide full-spectrum security for data in transit and at rest.