CGPSC MAINS 2016 Paper-4

Points to Remember: Ohm’s Law: V = IR (Voltage = Current x Resistance) Series Resistance: Rtotal = R1 + R2 + R3 … Parallel Resistance: 1/Rtotal = 1/R1 + 1/R2 + 1/R3 … Introduction: This question requires a factual and analytical approach to determine the equivalent resistance in Join Our Telegram Channel a simple circuit. … Read more

Points to Remember: Definition and characteristics of polytene chromosomes. Location of polytene chromosomes in nature. The significance of “puffs” or “Balbiani rings” in polytene chromosomes. Introduction: Polytene chromosomes are giant chromosomes found in certain tissues of some dipteran (two-winged) insects, such as Drosophila (fruit flies) and some plants. Unlike typical chromosomes, which consist of a … Read more

Points to Remember: Definition of isotopic effect. Isotopes of hydrogen: protium, deuterium, and tritium. Differences in properties due to mass difference. Examples of isotopic effects in chemical reactions and physical properties. Introduction: The isotopic effect refers to the difference in physical or chemical properties of isotopes of the same element. Isotopes are atoms of the … Read more

Points to Remember: Silicate impurities in iron ore are primarily removed through slag formation. This process involves chemical reactions between the impurities and fluxes added to the blast furnace. The slag is less dense than molten iron and floats on top, allowing for easy separation. Understanding the chemical reactions involved is crucial for efficient iron … Read more

Points to Remember: pH scale pOH scale [H⁺] and [OH⁻] concentrations Strong vs. weak acids and bases Neutralization reactions Introduction: The acidic or basic nature of a solution is a fundamental concept in chemistry. It describes the concentration of hydrogen ions (H⁺) and hydroxide ions (OH⁻) present in the solution. A solution’s acidity or basicity … Read more

Points to Remember: Plane mirrors produce virtual images. Plane mirrors produce laterally inverted images. Introduction: A plane mirror is a flat, smooth reflecting surface. When light rays strike a plane mirror, they reflect according to the law of reflection (the angle of incidence equals the angle of reflection). This reflection process creates an image, which … Read more

Points to Remember: Mendeleev’s periodic table organization. Number of groups and periods. Evolution of the periodic table. Introduction: Dmitri Mendeleev’s periodic table, first published in 1869, revolutionized the understanding of chemical elements. While his initial table differed from the modern version, it laid the crucial groundwork for organizing elements based on their atomic weight and … Read more