Important Formulas
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Important Formulas, Units & Definitions – CBSE & IGCSE
The ultimate resource for all-important formulas, key units, and definitions—your quick revision tool for CBSE & IGCSE. Perfect for board exams, Olympiads, JEE, NEET, NTSE, and daily homework. Use this to boost accuracy, save time, and master every subject!
How to Revise Formulas & Units?
- Make personalized flashcards or quick sticky notes for tough formulas and review them daily.
- Group similar formulas—such as motion/energy, acids/bases, area/volume, etc.—for quick association.
- Practice by writing and solving questions with the formulas; never memorize in isolation.
- Use memory tricks and mnemonics for complex definitions and lists.
- Before every test, do a “rapid-fire” recall session—speak or write as many formulas as you can remember.
Physics: Common Units & Measurements
Quantity | Unit (SI) | Symbol |
---|---|---|
Force | Newton | N |
Energy/Work | Joule | J |
Power | Watt | W |
Charge | Coulomb | C |
Potential Difference | Volt | V |
Frequency | Hertz | Hz |
Chemistry: Essential Units & Constants
Quantity | Unit/Symbol | Value/Notes |
---|---|---|
Amount of Substance | Mole (mol) | 6.022 x 1023 particles (Avogadro's Number) |
Concentration | mol/L | Molarity (M) |
Gas Constant | R | 8.314 J mol-1 K-1 |
Pressure | Pascal (Pa), atm | 1 atm = 101325 Pa |
Volume (gas) | dm3, L | 1 dm3 = 1 L |
Maths: Key Formula Categories & Units
Topic | Representative Formula | Unit (if any) |
---|---|---|
Area of Circle | A = πr² | m², cm² |
Quadratic Formula | x = (-b ± √(b²-4ac))/(2a) | — |
Slope of a Line | m = (y₂ - y₁)/(x₂ - x₁) | — |
Pythagoras Theorem | a² + b² = c² | units² |
Surface Area (Cuboid) | 2(lb + bh + hl) | m², cm² |
Biology: Essential Terms & Units
Process/Quantity | Unit/Scale | Key Notes |
---|---|---|
Cell Size | Micrometre (μm) | 1 μm = 10-6 m |
Enzyme Activity | Katal (kat) | Rate of catalysis |
Genetic Information | Base pairs | Measured in bp, kbp, Mbp |
Blood Volume (human) | Litre (L) | ~5 L in adults |
English: Key Literary & Grammar Terms
- Noun: Name of a person, place, thing, or idea.
- Simile: Comparison using 'like' or 'as' (e.g., "brave as a lion").
- Metaphor: Direct comparison without 'like' or 'as' (e.g., "time is a thief").
- Alliteration: Repetition of consonant sounds at the start of words ("She sells sea shells").
- Passive Voice: Subject receives the action ("The letter was written by her.").
- Tense: The time of action—past, present, future.
- Antonym: A word opposite in meaning ("hot" vs. "cold").
Social Science: Essential Terms & Measures
Term/Index | Meaning/Unit | Use |
---|---|---|
GDP | Gross Domestic Product (₹, $) | Economic output of a country |
Literacy Rate | % | % of people above age 7 who can read & write |
Democracy | System of government | People rule through voting |
Longitude/Latitude | Degrees (°) | Geographical location on earth |
Key Definitions Across Subjects
- Displacement (Physics): The shortest distance between initial and final position of an object, with direction.
- Oxidation (Chemistry): The process where a substance loses electrons (or gains oxygen).
- Reduction (Chemistry): The process where a substance gains electrons (or loses oxygen).
- Power (Physics): The rate at which work is done or energy is transferred (Power = Work/Time).
- Photosynthesis (Biology): The process by which green plants use sunlight to convert water and CO2 into glucose and O2.
- Allele (Biology): One of two or more alternative forms of a gene.
- Transpiration (Biology): Loss of water vapor from aerial parts of plants, mainly through stomata.
- Polynomials (Math): An algebraic expression consisting of variables and coefficients, involving only non-negative integer powers of variables.
- Probability (Math): A measure of how likely an event is to occur, ranging from 0 (impossible) to 1 (certain).
- Subject (English): The person or thing that performs the action in a sentence.
- Active Voice (English): When the subject performs the action (e.g., "He wrote a letter").
- Democracy (Social Science): A form of government where the people have the authority to choose their governing legislation.
- Secularism (Social Science): The principle of separation of the state from religious institutions.
- Market Economy (Social Science): An economic system in which supply and demand regulate production and labor as opposed to government intervention.
- Acceleration (Physics): The rate of change of velocity per unit time (a = Δv/Δt).
- Mole (Chemistry): The amount of substance containing Avogadro's number (6.022 × 1023) of particles.
- Genotype (Biology): The genetic constitution of an organism.
- Mean (Math): The sum of a set of numbers divided by the number of elements; also known as average.
- Quadratic Equation (Math): An equation of the form ax² + bx + c = 0, where a ≠ 0.
- Longitude (Social Science): The angular distance east or west of the Prime Meridian, measured in degrees.
- Metaphor (English): A figure of speech that describes an object or action as something else, even though it is not literally applicable.
- Biodegradable (Biology): Capable of being decomposed by bacteria or other living organisms.
- Enthalpy (Chemistry): A measure of the total energy of a thermodynamic system, including internal energy and the product of pressure and volume.
- Vector (Physics): A quantity that has both magnitude and direction.
Important Formula Sheets (Quick Access)
CBSE
- Science (6–10): View Sheet
- Maths (6–10): View Sheet
- Physics (11–12): View Sheet
- Chemistry (11–12): View Sheet
- Maths (11–12): View Sheet
- Biology (11–12): View Sheet
IGCSE
- Physics: View Sheet
- Chemistry: View Sheet
- Maths: View Sheet
- Add Maths: View Sheet
Other Boards (IB, ICSE, State Boards)
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Last modified: Monday, 7 July 2025, 7:34 PM