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This is an original, topic-wise digest of the science taught in NCERT Classes VI to X, written in our own words and sized to the CAPF recognition level. It is the static base for Index. The NCERT set is the approved primary source for science (see sources index); this page condenses it so a single read replaces a re-skim of nine textbooks. It does not reproduce NCERT text and is not a substitute for one careful first reading of the books.
The depth target is correct fact, correct unit, correct definition, plus the everyday application. It is not derivation depth. Where CAPF rewards a defence or security angle, that is flagged.
The official General Science clause asks for "general awareness, scientific temper, comprehension and appreciation of scientific phenomena of everyday observation, including new areas of importance such as Information Technology, Biotechnology, and Environmental Science." NCERT VI to X covers the everyday-science and biology core directly. The three new areas (IT, biotechnology, environmental science) are touched in NCERT X and supplemented from lucent static gk digest and the dedicated wiki notes.
- Distance is a scalar (total path); displacement is a vector (shortest, with direction). Speed is distance per time; velocity is displacement per time. Acceleration is rate of change of velocity, SI unit metre per second squared.
- Newton's three laws: first (inertia, a body stays at rest or in uniform motion unless a net external force acts), second (force equals mass times acceleration, F = ma; the SI unit of force is the newton), third (every action has an equal and opposite reaction).
- Momentum is mass times velocity (unit kilogram metre per second); it is conserved in the absence of external force. This explains recoil of a gun and rocket propulsion.
- Fuller treatment in physics everyday.
- Newton's universal law: every mass attracts every other mass with a force proportional to the product of masses and inversely proportional to the square of the distance between them.
- g (acceleration due to gravity) on Earth is about 9.8 metre per second squared; it is less on the Moon (about one-sixth). Mass is constant everywhere; weight (mass times g) changes with location.
- Free fall, and why all bodies fall at the same rate in vacuum (the feather and coin demonstration).
- Work is force times displacement in the direction of force; SI unit the joule. No work is done if there is no displacement.
- Kinetic energy is energy of motion (half m v squared); potential energy is stored energy of position (m g h). Energy is conserved, only transformed.
- Power is rate of doing work; SI unit the watt (one joule per second). One horsepower is about 746 watt. One kilowatt-hour (commercial unit of electricity) equals 3.6 million joule.
- Sound is a longitudinal mechanical wave; it needs a medium and cannot travel in vacuum. Speed in air is about 343 metre per second, faster in water and fastest in solids.
- Audible range for humans is roughly 20 hertz to 20,000 hertz. Below is infrasound; above is ultrasound (used in SONAR and medical scanning). Echo, reverberation and the use of ultrasound in cleaning and imaging.
- Light travels in straight lines; speed in vacuum about 3 times 10 to the power 8 metre per second. Reflection (mirrors) and refraction (bending on entering a new medium, the basis of lenses).
- Concave mirror converges, convex mirror diverges (used as vehicle rear-view because it gives a wider, erect, diminished image). Convex lens converges; concave lens diverges.
- The human eye, defects and their corrections: myopia (short-sight, corrected by concave lens), hypermetropia (long-sight, corrected by convex lens), presbyopia, cataract. Dispersion of white light into the spectrum by a prism explains the rainbow; the order is red to violet.
- Current is rate of flow of charge (ampere); potential difference is voltage (volt); resistance is opposition to flow (ohm). Ohm's law: voltage equals current times resistance (V = IR).
- Series versus parallel circuits; household wiring is parallel. Heating effect of current (the basis of the bulb filament, heater and fuse). Power equals voltage times current.
- A current-carrying conductor produces a magnetic field (Oersted). Electromagnetic induction (Faraday) is the basis of the generator and transformer. The electric motor converts electrical to mechanical energy; the generator does the reverse.
- Three states of matter (solid, liquid, gas) and changes of state (melting, freezing, evaporation, condensation, sublimation). Evaporation causes cooling.
- Heat transfer by conduction, convection and radiation. Temperature scales: Celsius, Fahrenheit and the SI Kelvin (zero kelvin is absolute zero, minus 273.15 degree Celsius).
- Matter is anything with mass and volume; it is particulate, with particles in constant motion and spaces between them. States differ in particle arrangement and energy.
- Pure substances (elements and compounds) versus mixtures (homogeneous like a solution; heterogeneous). Separation techniques: filtration, evaporation, distillation, chromatography, centrifugation.
- An atom has a central nucleus (protons, positively charged; neutrons, neutral) with electrons (negative) around it. Atomic number is the number of protons; mass number is protons plus neutrons.
- Isotopes (same atomic number, different mass number, for example carbon-12 and carbon-14). Models in sequence: Dalton, Thomson, Rutherford, Bohr.
- Valency and how atoms combine to satisfy the octet rule.
- Mendeleev arranged elements by atomic mass; the modern periodic law (Moseley) arranges by atomic number. Groups (vertical) share valency and properties; periods (horizontal). Metals on the left, non-metals on the right, metalloids between.
- Ionic bonds (transfer of electrons, for example sodium chloride) versus covalent bonds (sharing, for example water and methane).
- Acids release hydrogen ions in water and turn blue litmus red; bases release hydroxide ions and turn red litmus blue. The pH scale runs 0 to 14; 7 is neutral, below 7 acidic, above 7 basic.
- Neutralisation produces salt and water. Everyday examples: hydrochloric acid in the stomach, baking soda (sodium hydrogen carbonate), washing soda (sodium carbonate), bleaching powder, plaster of Paris.
- Metals are malleable, ductile, lustrous and good conductors; non-metals generally are not. The reactivity series ranks metals; more reactive metals displace less reactive ones.
- Corrosion (rusting of iron needs both air and moisture) and its prevention (galvanising, painting, alloying). Common alloys: brass (copper and zinc), bronze (copper and tin), steel and stainless steel.
- Carbon forms covalent compounds; allotropes diamond (hardest natural substance), graphite (conducts, used as lubricant) and fullerene. Saturated (alkanes) versus unsaturated hydrocarbons; homologous series; ethanol and ethanoic acid as everyday organic compounds. More in chemistry everyday.
- The cell is the basic structural and functional unit of life (cell theory, Schleiden, Schwann, Virchow). Robert Hooke first observed cells (in cork, 1665).
- Prokaryotic cells (no true nucleus, for example bacteria) versus eukaryotic cells (true nucleus). Key organelles: nucleus (control centre), mitochondria (the powerhouse, site of respiration), chloroplast (photosynthesis, in plants), ribosomes (protein synthesis), endoplasmic reticulum, Golgi apparatus, lysosomes (the suicide bag).
- Plant cells additionally have a cell wall (cellulose), a large vacuole and chloroplasts. See biology cell and classification.
- Plant tissues (meristematic and permanent) and animal tissues (epithelial, connective, muscular, nervous).
- The hierarchy of classification and binomial nomenclature (Carl Linnaeus); the five-kingdom system (Whittaker): Monera, Protista, Fungi, Plantae, Animalia.
- Nutrition: autotrophic (photosynthesis in green plants, converting carbon dioxide and water into glucose and oxygen using sunlight and chlorophyll) versus heterotrophic.
- Respiration: aerobic (with oxygen, full breakdown of glucose, more energy) versus anaerobic (without oxygen, producing lactic acid in muscles or ethanol in yeast).
- Transport: in humans the heart (four chambers) and the double circulation; in plants xylem (water and minerals up) and phloem (food, both ways).
- Excretion: kidneys as the main human organ; the nephron is the functional unit.
- Nervous control (brain, spinal cord, nerves; the reflex arc) and chemical control by hormones (the endocrine glands; insulin from the pancreas controls blood sugar; thyroxine from the thyroid; adrenaline). Plant hormones (auxin, gibberellin) and tropisms.
- Reproduction: asexual (binary fission, budding, vegetative propagation) versus sexual. Human reproductive system in outline.
- Gregor Mendel and the laws of inheritance; dominant and recessive traits. Genes are units of heredity on chromosomes; DNA carries the genetic code.
- Sex determination in humans (XX female, XY male). Basics of variation and Darwin's natural selection. Vocabulary continues in biotechnology and genetics.
- Balanced diet and the food components: carbohydrates, proteins, fats, vitamins, minerals, water and roughage. Deficiency diseases: scurvy (vitamin C), rickets (vitamin D), night blindness (vitamin A), beriberi (vitamin B1), anaemia (iron).
- Communicable diseases (spread by pathogens and vectors, for example malaria by the Anopheles mosquito, dengue by Aedes) versus non-communicable (diabetes, hypertension). Vaccination and immunity. Detail in nutrition diseases and health.
- Air, water and the atmosphere; the water cycle; the carbon, oxygen and nitrogen cycles. Pollution (air, water, soil, noise) and its sources and effects.
- Natural resources (coal, petroleum, natural gas as fossil fuels; renewables like solar, wind, hydro, biomass). Conservation, the three Rs (reduce, reuse, recycle).
- The ozone layer and its depletion (chlorofluorocarbons); the greenhouse effect and global warming. This block feeds environment and ecology and is the NCERT base for the new-area "Environmental Science."
NCERT VI to X is thin on three CAPF-relevant areas; fill these from the wiki notes and lucent static gk digest:
- Information Technology and computing (computer basics, internet, AI, cyber-security): see information technology and computing.
- Space and defence technology (ISRO, DRDO, missiles, nuclear basics): see space and defence technology. This is the CAPF defence angle.
- Latest scientific developments and current science affairs: track through current affairs, verify the latest from PIB.
Read NCERT science once for understanding, then revise from this digest and the general-science module. Do not derive formulae or memorise reaction mechanisms; CAPF asks for recognition. Prioritise: SI units and named laws (physics), everyday compounds and the pH and reactivity ideas (chemistry), life processes and deficiency diseases (biology), and the three new areas (IT, biotech, environment). The full strategy is in how to use the canon.
- NCERT Science textbooks, Classes VI to X (the primary source for this digest).
- Cross-checked against the wiki general-science module and the source policy in sources index.