Science – GK Questions

1 kWh = energy consumed by a 1 kW device running for 1 hour = 3.6×10⁶ Joules. Electricity bills use kWh. Understanding units is crucial for numerical problems. [[NCERT Physics Class 10]]

Alveoli are microscopic sacs surrounded by capillaries. Oxygen diffuses into blood, CO₂ diffuses out. Their large surface area (~70 m²) enables efficient respiration. Key anatomy concept. [[NCERT Biology Class 11]]

pH < 7 indicates acidic solution; pH > 7 is basic; pH = 7 is neutral. pH scale measures hydrogen ion concentration. Fundamental for acid-base chemistry in exams. [[NCERT Chemistry Class 10]]

Main ML types are supervised (labeled data), unsupervised (unlabeled patterns), and reinforcement (reward-based). 'Deterministic Learning' isn't a standard category; ML often deals with probabilistic outcomes. Emerging topic for tech-awareness sections. [[NITI Aayog Reports]]

Standard gravity (g) is 9.8 m/s², varying slightly with altitude and latitude. It's derived from Newton's law of gravitation (g = GM/R²). Essential for mechanics problems in physics. [[NCERT Physics Class 11]]

Decomposers break down dead organisms, recycling nutrients (nitrogen, phosphorus) into soil for producers. This sustains ecosystem productivity and is vital for biogeochemical cycles. [[NCERT Biology Class 12]]

Solids have fixed shape and volume due to strong intermolecular forces holding particles in fixed positions. Liquids have fixed volume but variable shape; gases have neither. Basic concept in matter classification. [[NCERT Chemistry Class 9]]

The 2015 Paris Agreement targets limiting global temperature rise to well below 2°C, preferably 1.5°C, to mitigate climate change impacts. India is a signatory committed to Nationally Determined Contributions (NDCs). [[UNFCCC, NCERT Geography Class 11]]

Myopia is corrected using concave (diverging) lenses. Convex (converging) lenses correct hypermetropia (farsightedness). Understanding lens applications is essential for optics questions in exams. [[NCERT Physics Class 10]]

The aorta is the main artery carrying oxygen-rich blood from the left ventricle to systemic circulation. Pulmonary artery carries deoxygenated blood to lungs. Critical for understanding human physiology. [[NCERT Biology Class 11]]

Carboxylic acids contain the carboxyl group (-COOH), which imparts acidic properties. Examples include acetic acid (vinegar) and citric acid. This group is central to organic chemistry reactions and biochemistry. [[NCERT Chemistry Class 12]]

Wi-Fi operates on 2.4 GHz or 5 GHz radio frequency bands to transmit data wirelessly between devices and routers. Understanding this helps in troubleshooting network issues and cybersecurity awareness. [[NCERT Computer Science]]

Acceleration (a = Δv/Δt) measures how quickly velocity changes. It's a vector quantity with SI unit m/s². Negative acceleration is deceleration. Fundamental in kinematics for physics exams. [[NCERT Physics Class 9]]

Transpiration is the evaporation of water from plant leaves via stomata. It aids in water uptake, nutrient transport, and cooling. Excessive transpiration can cause wilting. Key concept in botany. [[NCERT Biology Class 11]]

Rusting (formation of hydrated iron(III) oxide) is a chemical change involving oxidation of iron in presence of oxygen and water. It alters chemical composition, unlike physical changes like melting. Important for basic chemistry concepts. [[NCERT Chemistry Class 10]]

Photovoltaic (PV) cells in solar panels convert sunlight directly into electricity via the photovoltaic effect. This clean energy technology is promoted under India's National Solar Mission. [[MNRE Reports, NCERT Geography Class 11]]

A light year is the distance light travels in one year in vacuum (~9.46 trillion km). It's used in astronomy to measure vast interstellar distances, not time. Common trick question in exams. [[NCERT Physics Class 11]]

Prokaryotes (e.g., bacteria) lack a membrane-bound nucleus; their DNA floats in the nucleoid region. Eukaryotes (plants, animals) have a true nucleus. This distinction is fundamental in biology classification. [[NCERT Biology Class 11]]

Mercury (Hg) is the only metal liquid at standard room temperature (25°C) due to weak metallic bonding. It's used in thermometers, barometers, and electrical switches. Bromine is the only non-metal liquid at room temperature. [[NCERT Chemistry Class 10]]

HTTP (HyperText Transfer Protocol) is the foundation of data communication on the World Wide Web. It enables loading of web pages using hypertext links. HTTPS adds encryption for security. Crucial for computer awareness sections. [[NCERT Computer Science]]