Science Facts

Newton's First Law: An object remains at rest or in uniform motion unless acted upon by an external force. Second Law: Force equals mass times acceleration (F=ma). Third Law: Every action has an equal and opposite reaction.

Universal Law of Gravitation: F = G(m₁m₂)/r². G = 6.674 × 10⁻¹¹ N m²/kg². Earth's gravity: 9.8 m/s². Moon's gravity: 1.62 m/s² (1/6th of Earth's).

Law of Conservation of Energy: Energy cannot be created or destroyed, only transformed. Kinetic Energy = ½mv². Potential Energy = mgh. Power = Work/Time.

Sound travels faster in solids than in liquids and gases. Speed of sound in air: 343 m/s. Light travels at 3 × 10⁸ m/s in vacuum. Electromagnetic spectrum ranges from radio waves to gamma rays.

Ohm's Law: V = IR. Power = VI. Current is measured in amperes (A), voltage in volts (V), resistance in ohms (Ω). AC frequency in India: 50 Hz.

Atoms consist of protons (positive), neutrons (neutral), and electrons (negative). Atomic number = number of protons. Mass number = protons + neutrons. Isotopes have same atomic number but different mass numbers.

Modern periodic table has 118 elements. Groups: 18 vertical columns. Periods: 7 horizontal rows. Metals are on the left, non-metals on the right. Noble gases are in Group 18.

Ionic bonds form between metals and non-metals. Covalent bonds form between non-metals. Hydrogen bonds are weak bonds between hydrogen and electronegative atoms. Metallic bonds are between metal atoms.

pH scale ranges from 0 (acidic) to 14 (basic). Neutral pH is 7. Acids turn blue litmus red. Bases turn red litmus blue. Common acid: HCl. Common base: NaOH.

Types: Combination, Decomposition, Displacement, Double Displacement. Exothermic reactions release heat. Endothermic reactions absorb heat. Catalysts speed up reactions without being consumed.

Cell is the basic unit of life. Prokaryotic cells lack nucleus. Eukaryotic cells have nucleus. Cell organelles: Mitochondria (powerhouse), Golgi body (packaging), ER (transport), Lysosomes (digestion).

206 bones in adult human body. 640 muscles. 5 liters of blood in average adult. Heart beats 60-100 times per minute. Normal body temperature: 37°C (98.6°F).

Food path: Mouth → Esophagus → Stomach → Small Intestine → Large Intestine. Liver produces bile. Pancreas secretes insulin. Small intestine is 6-7 meters long.

Lungs contain 300-500 million alveoli. Normal breathing rate: 12-20 breaths per minute. Oxygen is carried by hemoglobin in red blood cells. CO₂ is transported as bicarbonate ions.

Brain weighs about 1.4 kg. Contains 86 billion neurons. Spinal cord is about 45 cm long. Nervous system controls all body functions. Reflex actions are automatic responses.

Food chain shows energy flow. Food web shows complex interactions. Producers (plants) → Consumers (animals) → Decomposers (bacteria/fungi). Energy is lost at each trophic level.

Types: Air, Water, Soil, Noise. Air Quality Index (AQI) measures air pollution. BOD (Biological Oxygen Demand) measures water pollution. Noise pollution is measured in decibels (dB).

Global warming is caused by greenhouse gases (CO₂, CH₄, N₂O). Earth's temperature has risen by 1.1°C since 1880. Sea levels rising at 3.3 mm per year. Paris Agreement aims to limit warming to 1.5°C.

India has 104 National Parks. 551 Wildlife Sanctuaries. 18 Biosphere Reserves. Project Tiger started in 1973. Project Elephant in 1992.

Solar energy is most abundant. Wind energy is fastest growing. Hydropower is most used renewable. India aims for 500 GW renewable energy by 2030. Nuclear energy is clean but non-renewable.

8 planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Sun's surface temperature: 5,500°C. Earth's distance from Sun: 150 million km. Moon's distance: 384,400 km.

First satellite: Aryabhata (1975). First Moon mission: Chandrayaan-1 (2008). First Mars mission: Mangalyaan (2013). First Sun mission: Aditya-L1 (2023). GSLV Mk III is heaviest rocket.

Satellites orbit at different heights: LEO (200-2000 km), MEO (2000-35786 km), GEO (35786 km). GPS uses 24 satellites. ISS orbits at 400 km. Space debris is a growing concern.

Milky Way has 100-400 billion stars. Andromeda is nearest galaxy. Light year = 9.46 trillion km. Black holes have infinite density. Big Bang occurred 13.8 billion years ago.

Gaganyaan: India's first manned mission. Chandrayaan-3: First soft landing near Moon's south pole. Aditya-L1: First Indian solar mission. NISAR: Joint NASA-ISRO Earth observation mission.

CPU is brain of computer. RAM is temporary memory. ROM is permanent memory. Binary system uses 0 and 1. 1 byte = 8 bits. 1 kilobyte = 1024 bytes.

TCP/IP is basic protocol. HTTP is for web pages. HTTPS is secure version. DNS converts domain names to IP addresses. IPv4 uses 32-bit addresses. IPv6 uses 128-bit addresses.

5G offers speeds up to 10 Gbps. 4G offers up to 100 Mbps. SIM card stores subscriber information. IMEI is unique device identifier. Mobile number portability allows changing operators.

Machine Learning is subset of AI. Deep Learning uses neural networks. Natural Language Processing enables human-computer interaction. Computer Vision enables image recognition.

Encryption protects data. Firewall blocks unauthorized access. VPN provides secure connection. Malware includes viruses, worms, trojans. Two-factor authentication adds security layer.