CGPSC MAINS 2015 Paper-4

Points to Remember: Pesticide resistance is the decreased susceptibility of a pest population to a pesticide that was previously effective. Resistance develops through natural selection, favoring resistant individuals within a pest population. Management strategies focus on delaying or mitigating resistance development. Integrated Pest Management (IPM) is a key approach to sustainable pesticide resistance management. Introduction: … Read more

Points to Remember: Definition and purpose of supercomputers. Architectural differences from regular computers. Key applications and industries using supercomputers. Limitations and challenges. Future trends and developments. Introduction: Supercomputers are high-performance computing systems designed to handle extremely complex calculations and simulations far beyond the capabilities of conventional computers. Unlike personal computers or even powerful servers, supercomputers … Read more

Points to Remember: Origins and Objectives of the policy Key areas of focus Implementation mechanisms Strengths and weaknesses Future directions Introduction: India’s National Policy on Science and Technology (NPST), while not a single, static document with a specific publication date, represents a continuous evolution of government strategies aimed at leveraging science and technology for national … Read more

Points to Remember: Population Explosion: Rapid increase in human population, its causes, consequences, and family welfare programs aimed at managing it. Earthquakes: Geological phenomenon, causes (tectonic plates), effects (destruction, casualties), and mitigation strategies. Introduction: The world faces two significant challenges: rapid population growth and the devastating impact of natural disasters like earthquakes. The global population … Read more

Points to Remember: Laboratory preparation of hydrogen gas. Isotopes of hydrogen: protium, deuterium, tritium. Differences and uses of hydrogen isotopes. Introduction: Hydrogen, the simplest element with atomic number 1, is a crucial element with diverse applications. It’s primarily prepared in laboratories through chemical reactions. Understanding its isotopes – atoms of the same element with varying … Read more

Points to Remember: Two important iron ores: Hematite (Fe₂O₃) and Magnetite (Fe₃O₄) Iron extraction involves reduction of iron oxides to metallic iron. The primary method is the Blast Furnace process. Introduction: Iron is a crucial element for modern civilization, forming the backbone of numerous industries. Its extraction from ores is a cornerstone of metallurgical engineering. … Read more

Points to Remember: Definition and types of polymers. Mechanism of polymerization (addition and condensation). Preparation and structure of rubber, PVC, and polythene. Introduction: Polymers are large molecules composed of repeating structural units called monomers. These monomers are linked together through a process called polymerization. Polymers are ubiquitous in modern life, forming the basis of plastics, … Read more

Points to Remember: Chemical equilibrium is a dynamic state where the rates of forward and reverse reactions are equal. Equilibrium is affected by changes in pressure, temperature, and concentration, following Le Chatelier’s principle. The effect of these changes depends on the stoichiometry of the reaction and whether it is exothermic or endothermic. Introduction: Chemical equilibrium … Read more

Points to Remember: Nuclear reactors utilize nuclear fission to generate heat. This heat is used to produce electricity or for other applications. Safety and waste disposal are crucial considerations. Different reactor designs exist, each with specific applications. Introduction: Nuclear reactors are devices that initiate and control sustained nuclear chain reactions. These reactions, primarily involving the … Read more

Points to Remember: Definition of cathode rays. Production method of cathode rays. Six key characteristics of cathode rays. Introduction: Cathode rays, discovered in the late 19th century, played a pivotal role in the understanding of atomic structure and the development of modern physics. They are streams of electrons, negatively charged subatomic particles, emitted from the … Read more