If you don't know what the Metric System (SI) is
| Quantity | Unit | Definition | Normalized | |
|---|---|---|---|---|
| Name | Symbol | |||
| Time | second | s | 9'192'631'770 periods of the radiation emitted by the ground-state hyperfine transition of the caesium 133 atom. | 1 s |
| minute | min | 60 seconds. | 60 s | |
| hour | h | 60 minutes. | 3600 s | |
| day (SI,ATI) | d day |
24 hours. | 86'400 s | |
| day (UTC) | d day |
24 hours, sometimes plus or minus 1 "leap" second. | 86'400(±01) s | |
| Length Distance Position along a line Displacement |
meter | m | 1/299'792'458 of the distance traveled by light in one second. | 1 m |
| angstrom | Å | 100 picometers. | 10−10 m | |
| astronomical unit | au | 149'597'870'700 meters. | 149'597'870'700 m | |
| inch | ′′ in |
25.4 millimeters. | 2.54 × 10−2 m | |
| foot | ′ ft |
12 inches. | 0.3048 m | |
| yard | yd | three feet. | 0.9144 m | |
| mile | mi | 1.609 344 kilometers. | 1609.344 m | |
| Area | square meter | m2 | Area of a square with sides of 1 meter. | 1 m2 |
| hectare | ha | Area of a square with sides of 100 meters. | 10'000 m2 | |
| acre | ac | 43'560 square feet. | 4046.856'422'40 m2 | |
| barn | b | 100 square femtometers. | 10−28 m2 | |
| Volume Capacity |
cubic meter | m3 | Volume of a cube with sides of 1 meter. | 1 m3 |
| liter | L dm3 |
1/1000 of a cubic meter. | 10−3 m3 | |
| Velocity, speed | meter per second | m/s | Speed of something that travels 1 meter in 1 second. | m s−1 |
| speed of light | c | Speed of light in vacuum. | 299'792'458 m s−1 | |
| Acceleration | meter per second squared | m/s2 | Acceleration of something whose speed increases by 1 meter per second in 1 second. | m s−2 |
| gal | Gal | 0.01 meters per second squared. | 0.01 m s−2 | |
| standard gravity | g0 | 9.80665 meters per second squared. | 9.80665 m s−2 | |
| Energy in any form | joule | J | 1/6'626'070'15 × 1042 times the energy of a photon of radiation with period 1 second. | 1 kg m2 s−2 |
| electronvolt | eV | 1.602'176'634 × 10−19 joules. | 1.602'176'634 × 10−19 kg m2 s−2 | |
| large calorie grand calorie food calorie | kcal Cal |
4184 joules. | 4184 kg m2 s−2 | |
| small calorie gram calorie |
cal | 4.184 joules. | 4.184 kg m2 s−2 | |
| Force | newton | N | Force that produces 1 joule of work when applied over a displacement of 1 meter. | 1 kg m s−2 |
| dyne | dyn | Force that accelerates one gram of mass by 1 centimeter per second squared. | 0.00001 kg m s−2 | |
| pound-force pound of force |
lbf | One pound of mass times the standard gravity. | 4.4482216152605 kg m s−2 | |
| Power | watt | W | Power equivalent to transfer or conversion of one joule of energy per second. | 1 kg m2 s−3 |
| Mass | gram | g | Mass that accelerates at 1000 meters per second squared when subjected to 1 newton of force. | 10−3 kg |
| dalton | Da | 1/12 of the mass of one atom of carbon-12 in the ground state. | 1.660'539'040(±20) × 10−27 kg | |
| tonne metric ton |
t | 1000 kilograms, or 1 megagram. | 103 kg | |
| pound (of mass) | lb | 0.45359237 kilograms. | 0.45359237 kg | |
| Density of a substance or material Mass concentration in a solution or mixture Solubility |
gram per cubic meter | g/m3 | Density of a material that has 1 gram of mass in each cubic meter. | 10−3 kg m−3 |
| gram per liter kilogram per cubic meter |
g/L kg/m3 |
Density of a material that has 1 kilogram of mass in each cubic meter. | 1kg m−3 | |
| gram per cubic centimeter tonne per cubic meter |
g/cm3 t/m3 |
Density of a material that has 1 gram of mass in each cubic centimeter. | 103 kg m−3 | |
| Plane angle Phase of a sinusoidal function Amount of rotation Latitude Longitude Azimuth Elevation |
radian | rad | Central angle spanned on a circle by an arc whose length is equal the radius. | 1 rad |
| turn | turn | Angle covered by a complete turn. | 2 π rad | |
| degree (of angle) | ° deg |
1/360 of a turn. | π/180 rad | |
| minute (of angle) | ′ min |
1/60 of a degree of angle. | π/10'800 rad | |
| second (of angle) | ′′ sec |
1/60 of a minute of angle. | π/648'000 rad | |
| Angular speed Phase rate of a sinusoidal function |
radian per second | rad/s | Angular speed of something that rotates through one radian in one second. | 1 rad/s |
| turn per second | turn/s | Angular speed of something that makes one full turn in one second. | 2 π rad/s | |
| degree per second | °/s deg/s |
Angular speed of something that rotates through one degree in one second. | π/180 rad/s | |
| rotations per minute | rpm | Angular speed of something that makes one full turn in one minute. | π/30 rad/s | |
| Solid angle | steradian | sr | Central solid angle spanned on a sphere by a region with the same area as a square whose side is the radius. | 1 sr |
| Count of cycles of a periodic process | cycle | cyc | One full cycle of the process. | 1 cyc |
| Frequency of a periodic process | hertz | Hz | Frequency of a periodic process that completes one full cycle in one second. | 1 cyc s−1 |
| Wavelength of a periodic space function Image resolution |
meter per cycle | m/cyc | Wavelength of a periodic wave that repeats after 1 meter in the direction normal to the wave . | 1 cyc−1 m |
| Periodicity of a periodic process | second per cycle | s/cyc | Periodicity of a periodic process that completes one full cycle in one second. | 1 cyc−1 s |
| Count of discrete particles (atoms, molecules, ions, nucleons, etc.) | particle | ptc | One particle. | 1/6.022'140'76 × 10−23 mol |
| mole | mol | 6.022'140'76 × 1023 particles | 1 mol | |
| Particle count per volume in a medium Molarity of a solution |
particle per cubic meter | ptc/m3 | Molarity of a solution or medium that has one particle of the relevant substance in each cubic meter, on average. | 1/6.022'140'76 × 10−23 mol m−3 |
| mole per liter molar |
mol/L M |
Molarity of a solution that has 1 mole of the relevant substance in each liter, on average. | 103 mol m−3 | |
| Rate of particle flow Reaction rate Radioactivity |
becquerel | Bq | Radioactivity of a sample that incurs in one nuclear decay event in each second on average. | 1/6.022'140'76 × 10−23 mol s−1 |
| particle per second | ptc/s | Rate of flow, reaction, or decay that amounts to one particle (atom, molecule, photon, etc.) in each second, on average. | 1/6.022'140'76 × 10−23 mol s−1 | |
| katal | kat | Rate of chemical reaction that amounts to one mole of the reaction equation per each second. | 1 mol s−1 | |
| Electric charge | elementary charge | e | Electric charge of one electron or one proton. | 1.602'176'634 × 10−19 s A |
| coulomb | C | 1/1.602'176'634 × 1019 times the elementary charge. | 1 s A | |
| Electric current | ampere | A | Electric current equivalent to a net flow of 1 coulomb of electric charge in one second. | 1 A |
| Electric potential difference Voltage |
volt | V | Electric potential difference that, when incurred by one coulomb of charge, changes its potential energy by one joule. | 1 kg m2 s−3 A−1 |
Last edited on 2024-07-09 11:50:21 by stolfi