Wikipedia:Vital articles/Level 4/Physical sciences

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Random level 4 vital article in Physical sciences

Vital articles is a list of subjects for which Wikipedia should have corresponding high-quality articles. It serves as a centralized watchlist to track the status of Wikipedia's most essential articles. This is one of eleven Level 4 sub-lists of ten thousand articles and is currently under construction.

Articles in the Vital list have their assessments labelled as:

• Featured articles
• Former featured articles
• A-class articles
• Good articles
• Delisted good articles
• Failed good article nominees
• B-class articles
• C-class articles
• Start-class articles
• Stub-class articles
• List-class articles
• Unassessed articles

The progress bar is auto-updated via category count, and the symbols and article counts are updated daily by User:cewbot. Please read the FAQ before modifying the article list.

This list is tailored to the English-language Wikipedia. There is also a list of ten thousand articles considered vital to Wikipedias of all languages.

For more information on this list and the process for adding articles please see the Frequently Asked Questions (FAQ) page.

Total 1,116 articles.

Class	#Articles
FA	75
GA	108
B	383
C	464
FFA	27
DGA	55
Start	86

This section contains 1100 articles.

Physical sciences

This section contains 1116 articles.

Science basics

This section contains 17 articles.

1. Science (Level 1)
2. Scientific method (Level 3)
3. Nature (Level 3)
4. Natural science
5. Data
6. Experiment
7. Field research
8. Information science
9. Methodology
10. Observation
11. Scientific law
12. Research (Level 3)
13. Scientific modelling
14. Scientific theory

Research methods

This section contains 3 articles.

1. Qualitative research
2. Quantitative research
3. Laboratory

Measurement

This section contains 67 articles.

This section contains units of measurement and articles on metrology. For the measured quantities, see Science and Mathematics sections. For timekeeping and navigation, see Everyday Life and Technology. For measurement errors, see Statistics section in Mathematics.

Measurement: General

This section contains 6 articles.

1. Measurement (Level 3)
2. Accuracy and precision
3. Metrology
4. Unit of measurement
   1. Natural units
      1. Planck units

Measurement systems

This section contains 4 articles.

1. Metric system
   1. International System of Units (Level 3)
2. United States customary units
3. Imperial units

Units of measurement

This section contains 57 articles.

Time

This section contains 7 articles.

1. Second
2. Minute
3. Hour
4. Day (Level 3)
5. Week
6. Month
7. Year (Level 3)

Dimensional space

This section contains 13 articles.

Length and distance

This section contains 9 articles.

1. Inch
2. Foot
3. Cubit
4. Metre
5. Mile
6. Nautical mile
7. Astronomical unit
8. Light-year
9. Parsec

Area

This section contains 2 articles.

1. Acre
2. Hectare

Volume

This section contains 2 articles.

1. Gallon
2. Litre

Mechanics

This section contains 13 articles.

Energy, power, force and pressure

This section contains 7 articles.

1. Atmosphere
2. Calorie
3. Electronvolt
4. Joule
5. Watt
6. Newton
7. Pascal

Mass

This section contains 5 articles.

1. Dalton (unit)
2. Kilogram
3. Ton
4. Pound
5. Ounce

Velocity

This section contains 1 article.

1. Knot

Angle

This section contains 3 articles.

1. Degree
2. Radian
3. Steradian

Light

This section contains 3 articles.

1. Candela
2. Lumen
3. Lux

Temperature

This section contains 3 articles.

1. Celsius
2. Fahrenheit
3. Kelvin

Electromagnetism

This section contains 8 articles.

1. Ampere
2. Farad
3. Coulomb
4. Hertz
5. Ohm
6. Siemens
7. Tesla
8. Volt

Quantity

This section contains 3 articles.

Amount of substance

This section contains 1 article.

1. Mole

Data

This section contains 2 articles.

1. Byte
2. Bit

Radioactivity

This section contains 3 articles.

1. Becquerel
2. Gray
3. Sievert

Other

This section contains 1 article.

1. Decibel

Astronomy

This section contains 196 articles.

For astronomical instruments, see Technology: Optical Technology.

Basics

This section contains 8 articles.

1. Astronomy (Level 2)
2. Astronomical object
3. Astrophysics
4. Extraterrestrial life

Observational astronomy

This section contains 4 articles.

1. Observatory
2. Luminosity
3. Magnitude
4. Extinction

Astronomical objects

This section contains 61 articles.

Solar System

This section contains 26 articles.

1. Solar System (Level 2)
2. Sun (Level 2)
3. Mercury (Level 3)
4. Venus (Level 3)
5. Earth (Level 1)
   1. Moon (Level 2)
6. Mars (Level 3)
7. Asteroid belt
   1. Ceres
8. Jupiter (Level 3)
   1. Io
   2. Europa
   3. Ganymede
   4. Callisto
9. Saturn (Level 3)
   1. Enceladus
   2. Titan
10. Uranus (Level 3)
11. Neptune (Level 3)
    1. Triton
12. Halley's Comet
13. Kuiper belt
    1. Pluto
    2. Eris
14. Oort cloud
15. Interplanetary medium

Notable stars

This section contains 10 articles.

1. Alpha Centauri
2. Arcturus
3. Betelgeuse
4. Canopus
5. Capella
6. Polaris
7. Procyon
8. Rigel
9. Sirius
10. Vega

Notable galaxies

This section contains 12 articles.

1. Local Group
   1. Milky Way (Level 3)
      1. Galactic Center
         1. Sagittarius A*
   2. Andromeda Galaxy
   3. Large Magellanic Cloud
   4. Small Magellanic Cloud
   5. Triangulum Galaxy
2. Centaurus A
3. Messier 87
4. Pinwheel Galaxy
5. Whirlpool Galaxy

Notable nebulae

This section contains 6 articles.

1. Carina Nebula
2. Crab Nebula
3. Eagle Nebula
4. Horsehead Nebula
5. Orion Nebula
6. Ring Nebula

Other notable objects

This section contains 7 articles.

1. 3C 273
2. Cygnus X-1
3. Hyades
4. Omega Centauri
5. Pleiades
6. Virgo Supercluster
   1. Virgo Cluster

Celestial mechanics and astrometry

This section contains 38 articles.

Celestial mechanics

This section contains 17 articles.

1. Celestial mechanics
2. Orbit
   1. Barycenter (astronomy)
   2. Tidal locking
3. Eclipse
   1. Lunar eclipse
   2. Solar eclipse
4. Kepler's laws of planetary motion
5. Lagrange point
6. Night

Orbital mechanics

This section contains 7 articles.

1. Orbital mechanics
2. Escape velocity
3. Geostationary orbit
4. Geosynchronous orbit
5. Gravitational acceleration
6. Gravity assist
7. Low Earth orbit

Celestial sphere

This section contains 8 articles.

1. Celestial sphere
2. Astronomical coordinate systems
   1. Equatorial coordinate system
3. Equinox
4. Ecliptic
5. Horizon
6. Solstice
7. Zodiac

Constellations

This section contains 8 articles.

1. Constellation
   1. Canis Major
   2. Cassiopeia
   3. Centaurus
   4. Crux
   5. Orion
   6. Ursa Major
   7. Ursa Minor

Astrometry

This section contains 5 articles.

1. Astrometry
2. Albedo
3. Cosmic distance ladder
4. Parallax
5. Photometry

Galactic astronomy and extragalactic astronomy

This section contains 28 articles.

Basics

This section contains 16 articles.

1. Outer space (Level 3)
2. Galaxy (Level 3)
3. Black hole (Level 3)
   1. Event horizon
   2. Stellar black hole
   3. Supermassive black hole
4. Galaxy groups and clusters
   1. Supercluster
5. Interstellar medium
6. Nebula
7. Dark nebula
8. Molecular cloud
9. Great Attractor
10. H II region
11. Void (astronomy)
12. Cosmic ray

Galaxy morphological classification

This section contains 7 articles.

1. Galaxy morphological classification
2. Spiral galaxy
   1. Barred spiral galaxy
3. Elliptical galaxy
4. Lenticular galaxy
5. Irregular galaxy
6. Dwarf galaxy

Active galactic nucleus

This section contains 5 articles.

1. Active galactic nucleus
   1. Blazar
   2. Quasar
   3. Radio galaxy
   4. Seyfert galaxy

Physical cosmology

This section contains 16 articles.

1. Physical cosmology (Level 3)
2. Universe (Level 2)
   1. Observable universe
   2. Chronology of the universe
      1. Ultimate fate of the universe
3. Big Bang (Level 3)
   1. Cosmic inflation
   2. Cosmic microwave background
4. Galaxy formation and evolution
5. Formation and evolution of the Solar System
   1. Nebular hypothesis
6. Dark matter
7. Dark energy
   1. Cosmological constant
8. Redshift
   1. Hubble's law

Planetary science

This section contains 14 articles.

1. Planet (Level 3)
   1. Terrestrial planet
   2. Giant planet
   3. Exoplanet
2. Natural satellite (Level 3)
3. Comet (Level 3)
4. Minor planet
   1. Asteroid (Level 3)
   2. Dwarf planet
   3. Meteoroid
5. Atmosphere
6. Meteor shower
7. Impact event
8. Ring system

Stellar astronomy

This section contains 31 articles.

1. Star (Level 3)
2. Variable star
   1. Supernova (Level 3)
      1. Gamma-ray burst
   2. Nova
   3. Pulsar
   4. Cepheid variable
3. Star system
   1. Planetary system
   2. Binary star
   3. Star cluster
4. Stellar classification
5. Stellar evolution
   1. Star formation
      1. Starburst galaxy
   2. Planetary nebula
   3. Protostar
   4. Main sequence
   5. Giant star
      1. Red giant
   6. Supergiant
   7. Wolf–Rayet star
   8. White dwarf
   9. Neutron star
6. Stellar kinematics
7. Stellar magnetic field
8. Stellar structure
9. Solar wind
10. Metallicity
11. Brown dwarf
12. Hertzsprung–Russell diagram

Chemistry

This section contains 274 articles.

For biochemistry and chemical biology, see: Biology and health sciences; for chemical industry, see: Technology.

Chemistry: General

This section contains 23 articles.

1. Chemistry (Level 2)
2. Organic chemistry (Level 3)
3. Inorganic chemistry (Level 3)
4. Physical chemistry (Level 3)
5. Electrochemistry
   1. Electrolysis
6. Environmental chemistry
7. Medicinal chemistry
8. Nuclear chemistry
   1. Nuclide
9. Organometallic chemistry
10. Phase diagram
11. Photochemistry
12. Polymer chemistry
    1. Polymer
13. Quantum chemistry
14. Materials science
15. Alchemy
16. Substance (chemistry) (Level 3)
    1. Amount of substance
17. Chemical synthesis
18. Conservation of mass
19. pH

Chemical reactions

This section contains 15 articles.

1. Chemical reaction (Level 3)
   1. Acid–base reaction
   2. Catalysis (Level 3)
   3. Chemical equation
   4. Chemical equilibrium
   5. Chemical formula
   6. Chemical kinetics
   7. Redox
      1. Combustion
         1. Fire (Level 2)
      2. Corrosion
   8. Haber process
   9. Radical
   10. Reaction mechanism
   11. Substitution reaction

Chemical bonds

This section contains 8 articles.

1. Chemical bond (Level 3)
   1. Molecule (Level 3)
   2. Ionic bonding
   3. Covalent bond
   4. Metallic bonding
   5. Intermolecular force
      1. Hydrogen bond
   6. Valence bond theory

Separation processes

This section contains 3 articles.

1. Chromatography
2. Distillation
3. Filtration

Analytical chemistry

This section contains 4 articles.

1. Analytical chemistry (Level 3)
2. Spectroscopy
   1. Absorption spectroscopy
3. Mass spectrometry

Chemical substances

This section contains 221 articles.

Chemical elements

This section contains 117 articles.

Basics

This section contains 5 articles.

1. Chemical element (Level 2)
2. Periodic table (Level 3)
3. Allotropy
4. Atomic number
5. Atomic mass

Chemical element groups

This section contains 10 articles.

1. Metal (Level 3)
2. Alkali metal
3. Alkaline earth metal
4. Lanthanide
5. Actinide
6. Transition metal
7. Metalloid
8. Halogen
9. Noble gas
10. Synthetic element

Chemical elements

This section contains 102 articles.

1. Hydrogen (Level 3)
2. Helium
3. Lithium
4. Beryllium
5. Boron
6. Carbon (Level 3)
   1. Diamond
   2. Graphite
   3. Carbon nanotube
7. Nitrogen (Level 3)
8. Oxygen (Level 3)
   1. Ozone
9. Fluorine
10. Neon
11. Sodium
12. Magnesium
13. Aluminium
14. Silicon (Level 3)
15. Phosphorus
16. Sulfur
17. Chlorine
18. Argon
19. Potassium
20. Calcium
21. Scandium
22. Titanium
23. Vanadium
24. Chromium
25. Manganese
26. Iron (Level 3)
27. Cobalt
28. Nickel
29. Copper (Level 3)
30. Zinc
31. Gallium
32. Germanium
33. Arsenic
34. Selenium
35. Bromine
36. Krypton
37. Rubidium
38. Strontium
39. Yttrium
40. Zirconium
41. Niobium
42. Molybdenum
43. Technetium
44. Ruthenium
45. Rhodium
46. Palladium
47. Silver (Level 3)
48. Cadmium
49. Indium
50. Tin
51. Antimony
52. Tellurium
53. Iodine
54. Xenon
55. Caesium
56. Barium
57. Lanthanum
58. Cerium
59. Praseodymium
60. Neodymium
61. Promethium
62. Samarium
63. Europium
64. Gadolinium
65. Terbium
66. Dysprosium
67. Holmium
68. Erbium
69. Thulium
70. Ytterbium
71. Lutetium
72. Hafnium
73. Tantalum
74. Tungsten
75. Rhenium
76. Osmium
77. Iridium
78. Platinum
79. Gold (Level 3)
80. Mercury (element)
81. Thallium
82. Lead
83. Bismuth
84. Polonium
85. Astatine
86. Radon
87. Francium
88. Radium
89. Actinium
90. Thorium
91. Protactinium
92. Uranium
93. Neptunium
94. Plutonium
95. Americium
96. Curium
97. Berkelium
98. Californium

Chemical compounds

This section contains 86 articles.

Chemical compounds: General

This section contains 3 articles.

1. Chemical compound (Level 3)
   1. Inorganic compound
   2. Organic compound

Inorganic compounds

This section contains 22 articles.

1. Water (Level 2)
   1. Properties of water
   2. Ice
   3. Water vapor
2. Oxide
   1. Carbon dioxide (Level 3)
   2. Carbon monoxide
   3. Nitrous oxide
   4. Titanium dioxide
3. Hydrogen peroxide
4. Cyanide
5. Acid (Level 3)
   1. Boric acid
   2. Hydrochloric acid
   3. Hydrofluoric acid
   4. Nitric acid
   5. Phosphoric acid
   6. Sulfuric acid
6. Base (Level 3)
   1. Ammonia
   2. Potassium hydroxide
   3. Sodium hydroxide

Salts

This section contains 20 articles.

1. Salt (chemistry)
2. Carbonate
   1. Calcium carbonate
   2. Sodium bicarbonate
   3. Sodium carbonate
3. Chloride
   1. Calcium chloride
   2. Polyvinyl chloride
   3. Sodium chloride
4. Nitrate
   1. Ammonium nitrate
   2. Potassium nitrate
   3. Sodium nitrate
5. Silicate
   1. Sodium silicate
6. Sulfate
   1. Alum
   2. Sodium sulfate
   3. Ammonium sulfate
   4. Magnesium sulfate

Organic compounds

This section contains 6 articles.

1. Haloalkane
2. Organophosphorus chemistry
3. Organosilicon chemistry
   1. Silicone
4. Organosulfur chemistry
   1. Thiol

Carbon–nitrogen bond

This section contains 4 articles.

1. Amide
   1. Urea
   2. Nylon
2. Amine

Carbon–oxygen bond

This section contains 16 articles.

1. Alcohol
   1. Ethanol
   2. Methanol
2. Aldehyde
   1. Formaldehyde
3. Carboxylic acid
   1. Acetic acid
   2. Citric acid
   3. Lactic acid
4. Ester
   1. Polyester
5. Ether
6. Ketone
   1. Acetone
7. Phenol
   1. Tannin

Hydrocarbons

This section contains 15 articles.

1. Hydrocarbon
2. Alkane
   1. Butane
   2. Ethane
   3. Methane
   4. Propane
3. Alkene
   1. Ethylene
      1. Polyethylene
   2. Propylene
      1. Polypropylene
4. Aromatic compound
   1. Benzene
5. Alkyne
6. Oil

Chemical mixtures

This section contains 18 articles.

Chemical mixtures: General

This section contains 12 articles.

1. Alloy (Level 3)
2. Mixture
3. Aerosol
4. Amalgam
5. Colloid
6. Dispersion
7. Emulsion
8. Foam
9. Gel
10. Solution
11. Suspension
12. Syngas

Specific alloys

This section contains 6 articles.

1. Brass
2. Bronze (Level 3)
3. Cast iron
4. Steel (Level 3)
   1. Stainless steel
5. Wrought iron

Earth science

This section contains 267 articles.

For specific geographical places, see: Geography.

Basics

This section contains 2 articles.

1. Earth science (Level 3)
2. Natural resource

Natural disasters

This section contains 8 articles.

1. Natural disaster (Level 3)
2. Earthquake (Level 3)
3. Flood (Level 3)
4. Drought
5. Avalanche
6. Landslide
7. Tsunami
8. Wildfire

Earth

This section contains 165 articles.

Earth: General

This section contains 1 article.

1. Internal structure of Earth (Level 3)

Geology

This section contains 51 articles.

1. Geology (Level 2)
2. Plate tectonics (Level 3)
3. Fold
4. Meteorite
   1. Impact crater
5. Lithosphere
   1. Crust
   2. Fault
6. Stratigraphy
7. Thrust fault

Mineralogy

This section contains 11 articles.

1. Mineral (Level 3)
2. Mineralogy
3. Gemstone
4. Feldspar
5. Kaolinite
6. Pyroxene
7. Quartz
8. Talc
9. Mica
10. Gypsum
11. Asbestos

Mineral gemstones

This section contains 4 articles.

1. Emerald
2. Jade
3. Sapphire
4. Ruby

Organic gemstones

This section contains 3 articles.

1. Amber
2. Ivory
3. Pearl

Petrology

This section contains 23 articles.

1. Petrology
2. Rock (Level 3)
   1. Ore
3. Igneous rock
   1. Basalt
   2. Granite
   3. Magma
   4. Tuff
4. Sedimentary rock
   1. Limestone
   2. Clay
   3. Sand
   4. Oil shale
   5. Sandstone
   6. Bauxite
5. Metamorphic rock
   1. Schist
   2. Marble
   3. Gneiss
   4. Slate
6. Conglomerate
7. Breccia
8. Gravel

Geophysics

This section contains 8 articles.

1. Geodesy
2. Geophysics
3. Earth's inner core
4. Earth's magnetic field
5. Earth's outer core
6. Earth's mantle
7. Earth's crust
8. Seismology

Geomorphology

This section contains 51 articles.

1. Geomorphology
2. Erosion (Level 3)
3. Weathering

Landforms

This section contains 11 articles.

1. Landform
2. Land (Level 2)
3. Mountain (Level 3)
4. Mountain pass
5. Mountain range
6. Hill
7. Valley
8. Plateau
9. Mesa
10. Plain
11. Sedimentary basin

Fluvial landforms

This section contains 9 articles.

1. Alluvial fan
2. Beach
3. Canyon
4. Cliff
5. Floodplain
6. Meander
7. Oasis
8. Rapids
9. Waterfall

Glacial landforms

This section contains 3 articles.

1. Glacial landform
2. Fjord
3. Moraine

Caves

This section contains 2 articles.

1. Cave
2. Karst

Oceanic and coastal landforms

This section contains 12 articles.

1. Abyssal plain
2. Archipelago
3. Bay
4. Coast
5. Continental shelf
6. Coral reef
   1. Atoll
7. Lagoon
8. Oceanic trench
9. Peninsula
10. Island (Level 3)
11. Seamount

Volcanic landforms

This section contains 6 articles.

1. Volcano (Level 3)
2. Geyser
3. Hot spring
4. Hotspot
5. Lava
6. Mid-ocean ridge

Aeolian landforms

This section contains 2 articles.

1. Aeolian processes
2. Dune

Artificial landforms

This section contains 3 articles.

1. Artificial island
2. Land reclamation
3. Polder

Geological history

This section contains 28 articles.

1. History of Earth (Level 3)
   1. Geological history of Earth
2. Geochronology
3. Geologic time scale
4. Great Oxidation Event
5. Cambrian explosion
6. Extinction event
   1. Late Ordovician mass extinction
   2. Late Devonian mass extinction
   3. Permian–Triassic extinction event
   4. Triassic–Jurassic extinction
   5. Cretaceous–Paleogene extinction event
7. Ice age
8. Pangaea

Geological periods

This section contains 14 articles.

1. Precambrian
2. Phanerozoic
   1. Paleozoic
      1. Cambrian
      2. Permian
   2. Mesozoic
      1. Triassic
      2. Jurassic
      3. Cretaceous
   3. Cenozoic
      1. Paleogene
      2. Neogene
      3. Quaternary
         1. Holocene

Biomes

This section contains 19 articles.

1. Desert (Level 3)
2. Tundra
3. Shrubland

Forests

This section contains 7 articles.

1. Forest (Level 3)
2. Jungle
3. Mangrove
4. Taiga
5. Rainforest
   1. Tropical rainforest
6. Temperate broadleaf and mixed forests

Grasslands

This section contains 5 articles.

1. Grassland (Level 3)
2. Meadow
3. Prairie
4. Savanna
5. Steppe

Wetlands

This section contains 4 articles.

1. Wetland
2. Swamp
3. Marsh
4. Bog

Pedology

This section contains 7 articles.

1. Soil (Level 3)
   1. Peat
2. Soil formation
3. Pedosphere
4. Sediment
5. Soil fertility
6. Soil science

Air

This section contains 61 articles.

Atmosphere

This section contains 9 articles.

1. Atmosphere of Earth (Level 2)
2. Air mass
3. Atmospheric pressure
4. Atmospheric science
5. Ozone depletion

Atmospheric optics

This section contains 4 articles.

1. Aurora
2. Mirage
3. Rainbow
4. Sky

Climatology

This section contains 9 articles.

1. Climatology
2. Climate (Level 2)
3. Climate change (Level 3)
   1. Greenhouse effect
4. Climate variability and change
5. El Niño–Southern Oscillation
6. Köppen climate classification
7. Temperate climate
8. Tropical climate

Meteorology

This section contains 43 articles.

Meteorology: General

This section contains 6 articles.

1. Meteorology
2. Weather (Level 3)
3. Weather front
4. Weather forecasting
5. Humidity
6. Low-pressure area

Clouds

This section contains 5 articles.

1. Cloud (Level 3)
2. Cirrus cloud
3. Cumulonimbus cloud
4. Cumulus cloud
5. Fog

Precipitation

This section contains 7 articles.

1. Precipitation
2. Rain (Level 3)
3. Snow (Level 3)
4. Acid rain
5. Hail
6. Dew
7. Frost

Seasons

This section contains 7 articles.

1. Season (Level 3)
2. Spring (season)
3. Summer
4. Autumn
5. Winter
6. Dry season
7. Wet season

Atmospheric circulation

This section contains 7 articles.

1. Atmospheric circulation
2. High-pressure area
3. Cyclone
4. Extratropical cyclone
5. Hadley cell
6. Polar vortex
7. Walker circulation

Storms

This section contains 7 articles.

1. Storm (Level 3)
2. Tornado
3. Tropical cyclone (Level 3)
4. Blizzard
5. Dust storm
6. Lightning (Level 3)
7. Thunderstorm

Winds

This section contains 4 articles.

1. Wind (Level 3)
2. Jet stream
3. Monsoon
4. Trade winds

Water

This section contains 31 articles.

Water: General

This section contains 2 articles.

1. Hydrosphere
2. Cryosphere

Glaciology

This section contains 6 articles.

1. Glacier
2. Ice sheet
3. Ice shelf
4. Iceberg
5. Sea ice
6. Permafrost

Oceanography

This section contains 9 articles.

1. Oceanography
2. Sea (Level 3)
3. Ocean (Level 2)
4. Tide
5. Sea level
6. Seabed
7. Strait
8. Ocean current
9. Thermohaline circulation

Hydrology

This section contains 14 articles.

1. Hydrology
2. Water cycle
3. Body of water
4. Groundwater
   1. Spring (hydrology)
5. Hydrography
6. Limnology
7. Lake (Level 3)
   1. Dry lake
   2. Pond
8. River (Level 3)
   1. Drainage basin
   2. Estuary
   3. River delta

Physics

This section contains 295 articles.

Basics

This section contains 24 articles.

1. Physics (Level 2)
2. Energy (Level 2)
   1. Conservation of energy
3. Matter (Level 2)
   1. Atom (Level 3)
4. Force (Level 3)
5. Fundamental interaction
   1. Electromagnetism (Level 3)
   2. Gravity (Level 3)
   3. Strong interaction (Level 3)
   4. Weak interaction (Level 3)
6. Spacetime
   1. Space (Level 3)
      1. Vacuum (Level 3)
   2. Time (Level 2)
7. Mass–energy equivalence
8. Quantum gravity
9. Radiation
   1. Ionizing radiation
10. Field (physics)
    1. Flux
11. Gauge theory
12. Symmetry (physics)
13. Theoretical physics

Atomic, molecular and optical physics

This section contains 21 articles.

Atomic physics

This section contains 11 articles.

1. Atomic physics
2. Atomic orbital
3. History of atomic theory
4. Binding energy
5. Bohr model
6. Bremsstrahlung
7. Electron configuration
8. Electron shell
9. Energy level
10. Rutherford scattering experiments
11. Ion

Molecular physics

This section contains 2 articles.

1. Molecular orbital
2. Molecular orbital theory

Optics

This section contains 8 articles.

1. Optics (Level 3)
2. Focus
   1. Focal length
3. Polarization
4. Reflection
5. Refraction
   1. Refractive index
6. Transparency and translucency

Color

This section contains 17 articles.

Basics

This section contains 6 articles.

1. Color (Level 3)
2. CMYK color model
3. Color theory
   1. Primary color
4. Gloss (optics)
5. RGB color model

Color terms

This section contains 11 articles.

1. White
2. Black
3. Grey
4. Red
5. Orange
6. Yellow
7. Green
8. Blue
9. Pink
10. Purple
11. Brown

Condensed matter physics

This section contains 24 articles.

Basics

This section contains 3 articles.

1. Condensed matter physics
2. Solid-state physics
3. Amorphous solid

Crystallography

This section contains 3 articles.

1. Crystallography
2. Crystal
3. Crystallization

States of matter

This section contains 8 articles.

1. State of matter (Level 3)
2. Solid (Level 3)
3. Liquid (Level 3)
4. Gas (Level 3)
   1. Vapor
5. Plasma (Level 3)
6. Degenerate matter
7. Bose–Einstein condensate

Phase transitions

This section contains 10 articles.

1. Phase transition
2. Phase
3. Boiling
4. Melting
5. Freezing
6. Evaporation
7. Condensation
8. Ionization
9. Critical point
10. Triple point

Electromagnetism

This section contains 47 articles.

Basics

This section contains 10 articles.

1. Electricity (Level 2)
2. Magnetism (Level 3)
   1. Ferromagnetism
3. Magnet
   1. Electromagnet
4. Dielectric
5. Dipole
6. Metamaterial
7. Oil drop experiment
8. Photoelectric effect

Electrostatics

This section contains 6 articles.

1. Electrostatics
2. Coulomb's law
3. Electric charge
4. Electric field
5. Electric potential
   1. Voltage

Electrodynamics

This section contains 16 articles.

1. Electromagnetic radiation (Level 3)
   1. Electromagnetic spectrum
   2. Radio wave
   3. Microwave
   4. Infrared
   5. Light (Level 3)
      1. Visible spectrum
   6. Ultraviolet
   7. X-ray
   8. Fluorescence
2. Electromagnetic field
3. Electromagnetic induction
4. Electromotive force
5. Lorentz force
6. Eddy current
7. Maxwell's equations

Magnetism

This section contains 2 articles.

1. Magnetic field
2. Magnetostatics

Electrical circuits

This section contains 13 articles.

1. Electric current
   1. Alternating current
   2. Direct current
2. Electrical network
3. Electrical impedance
4. Electrical resistance and conductance
   1. Ohm's law
5. Capacitance
6. Semiconductor (Level 3)
7. Superconductivity
8. Gain (electronics)
9. Inductance
10. Kirchhoff's circuit laws

Mechanics

This section contains 86 articles.

Basics

This section contains 9 articles.

1. Mechanics
   1. Ballistics
   2. Continuum mechanics
   3. Kinematics
   4. Relativistic mechanics
   5. Statics
2. Oscillation
   1. Harmonic oscillator
      1. Simple harmonic motion

Quantum mechanics

This section contains 11 articles.

1. Quantum mechanics (Level 3)
2. Pauli exclusion principle
3. Quantum chromodynamics
4. Quantum electrodynamics
5. Quantum entanglement
6. Quantum field theory
7. Quantum tunnelling
8. Schrödinger equation
9. Uncertainty principle
10. Wave function
11. Wave–particle duality

Theory of relativity

This section contains 10 articles.

1. Theory of relativity (Level 3)
2. General relativity
3. Special relativity
4. Principle of relativity
5. Equivalence principle
6. Gravitational singularity
7. Gravitational wave
8. Lorentz transformation
9. Michelson–Morley experiment
10. Speed of light (Level 3)

Classical mechanics

This section contains 29 articles.

1. Classical mechanics (Level 3)
   1. Hamiltonian mechanics
   2. Lagrangian mechanics
2. Mass (Level 3)
   1. Density
3. Momentum
4. Motion (Level 3)
   1. Newton's laws of motion (Level 3)
   2. Speed
   3. Acceleration
   4. Velocity (Level 3)
   5. Equations of motion
5. Kinetic energy
6. Potential energy
7. Inertia
8. Moment of inertia
9. Friction
10. Impulse
11. Power
12. Work
13. Rotation
    1. Angular momentum
    2. Centripetal force
    3. Coriolis force
14. Torque
15. Weight
    1. Weighing scale
16. Frame of reference
17. Newton's law of universal gravitation

Fluid mechanics

This section contains 16 articles.

1. Fluid mechanics
2. Fluid dynamics
   1. Aerodynamics
3. Bernoulli's principle
4. Buoyancy
5. Convection
6. Drag
7. Diffusion
8. Flight
9. Lift (force)
10. Navier–Stokes equations
11. Osmosis
12. Reynolds number
13. Surface tension
14. Turbulence
15. Viscosity

Solid mechanics

This section contains 10 articles.

1. Solid mechanics
2. Deformation
3. Elastic modulus
4. Elasticity
5. Fatigue
6. Hooke's law
7. Plasticity
8. Stiffness
9. Strength of materials
10. Stress (mechanics)

Statistical mechanics

This section contains 1 article.

1. Statistical mechanics

Nuclear physics

This section contains 10 articles.

1. Atomic nucleus
2. Nuclear physics
3. Isotope
4. Nuclear fission
5. Nuclear fusion
6. Nucleosynthesis
7. Radioactive decay (Level 3)
   1. Alpha particle
   2. Beta particle
   3. Gamma ray

Particle physics

This section contains 35 articles.

Particle physics: General

This section contains 13 articles.

1. Particle physics (Level 3)
2. Standard Model (Level 3)
3. Physics beyond the Standard Model
   1. String theory
   2. Supersymmetry
4. Particle
5. Particle accelerator
   1. Large Hadron Collider
   2. Tevatron
6. Particle detector
7. Cloud chamber
8. Scattering
9. Spin

Subatomic particles

This section contains 19 articles.

1. Subatomic particle (Level 3)

Fermions

This section contains 12 articles.

1. Fermion
2. Lepton
   1. Electron (Level 3)
   2. Muon
   3. Tau
   4. Neutrino
3. Quark
4. Hadron
   1. Baryon
      1. Neutron (Level 3)
      2. Proton (Level 3)
   2. Meson

Bosons

This section contains 6 articles.

1. Boson
2. Gauge boson
   1. Photon (Level 3)
   2. Gluon
   3. W and Z bosons
3. Higgs boson

Antimatter

This section contains 3 articles.

1. Antimatter
2. Antiparticle
   1. Positron

Thermodynamics

This section contains 16 articles.

1. Thermodynamics (Level 3)
2. Heat
3. Temperature (Level 3)
   1. Absolute zero
4. Pressure
5. Laws of thermodynamics
6. Heat capacity
7. Heat transfer
8. Entropy
9. Enthalpy
10. Black-body radiation
11. Internal energy
12. Thermodynamic cycle
13. Thermodynamic free energy
14. Ideal gas law
15. Explosion

Waves

This section contains 15 articles.

1. Wave (Level 3)
2. Acoustics
   1. Sound (Level 3)
      1. Speed of sound
   2. Ultrasound
3. Amplitude
4. Frequency
5. Wavelength
6. Diffraction
7. Doppler effect
8. Wave interference
9. Noise
10. Resonance
11. Superposition principle
12. Wave equation