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Posted: Sun Jun 04, 2006 3:48 pm
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Upon some suggestions, we thought it best to include this to help you while navigating through the Physics Guild. Here you will find a list of short forms and some general terms for all things which we deemed useful and necessary. If you feel there is something omitted, please tell us in this thread, and if you are unfamiliar with a short form which someone has used but is not found here, please also tell us in this thread so that we may include it. This list will continually be updated. Each list is in alphabetical order.
Last revision: 23 Jun 2006 ~ Vorpal
General Terms EM - Electromagnetism (or electromagnetic) EWSB - Electroweak symmetry breaking GTR / GR - General Theory of Relativity HUP - Heisenberg's uncertainy principle PEP - Pauli's exclusion principle QCD - Quantum chromodynamics QED - Quantum electrodynamics QFT - Quantum field theory QM - Quantum mechanics RQM - Relativistic quantum mechanics STR / SR - Special Theory of Relatvity
SI prefixes
Factor==Exponent Form==Prefix (Symbol) 10^24==E24==yotta (Y) 10^21==E21==zetta (Z) 10^18==E18==exa (E) 10^15==E15==peta (P) 10^12==E12==tera (T) 10^9==E9==giga (G) 10^6==E6==mega (M) 10^3==E3==kilo (k) 10^2==E2==hecto (h) 10^1==E1==deca (da) 10^-1==E-1==deci (d) 10^-2==E-2==centi (c) 10^-3==E-3==milli (m) 10^-6==E-6==micro (µ) 10^-9==E-9==nano (n) 10^-12==E-12==pico (p) 10^-15==E-15==femto (f) 10^-18==E-18==atto (a) 10^-21==E-21==zepto (z) 10^-24==E-24==yocto (y)
A comparison of SI units with cgs and U.S. customary units follows. Values marked with ≡ are exact, either directly by definition or by inference from other definitions. The uncertainty is in reference to the last given digits, so that 6.0221415e23 with uncertainty 10 means (6.0221415±0.0000010)e23.
Dimensionless mole (mol): 1 mol = 6.0221415e23 units (uncertainty 10) [Avogadro's number]
Length SI unit: meter (m) angstrom (Å): 1 Å ≡ 100 pm ≡ 1e-10 m astronomical unit (AU): 1 AU = 1.49597870691e11 m (uncertainty 30) centimeter (cm): 100 cm ≡ 1m inch (in): 1 in ≡ 2.54 cm ≡ 0.0254 m fermi (fm): 1 fm ≡ 1e-15 m [femtometer] foot (ft): 1 ft ≡ 12 in ≡ 0.3048 m light-year [ly]: 1 ly = 5.8786e12 mi = 6.3241e4 AU = 9.4607e15 m mile (mi): 1 mi ≡ 1.609344 km ≡ 1.609344e3 m
[ly] By definition, 1 ly ≡ (31557600s)(299792458m/s), in reference to a Julian year.
Mass SI unit: kilogram (kg), rather than gram electron (m_e): 1 m_e = 0.510998918 MeV (U44) = 9.1093826e-31kg (U16) electron-volt (eV/c²): 1 eV/c² = 1.78266181e-36 kg (uncertainty 15) gram: 1000 g ≡ 1 kg pound-mass (lbm): 1 lbm ≡ 0.45359237 kg
Time SI unit: second (s) Hertz (Hz): 1 Hz ≡ 1/s year (tropical): 365.242190 days = 3.15569252e7 s year (Julian): 365.25 days ≡ 3.1557600e7 s
Temperature SI Unit: kelvin (K) Celcius (°C): C ≡ (5/9)(F - 32) = K - 273.15 Farenheit (°F): F ≡ (9/5)C + 32 Rankine (°R): R ≡ (9/5)K = F + 459.67
Force SI Units: newton (N), defined as kg·m/s². dyne (dyn): 1e5 dyn ≡ 1 N pound-force (lbf): 1 lbf ≡ 4.4482216152605 N poundal (pdl): 1 pdl ≡ 1 lb·ft/s² ≡ 0.138254954376 N relativistic limit: c⁴/(4G) = 3.0257e43N, uncertainty 5
Pressure SI Unit: pascal (Pa), defined as N/m² ≡ kg/(m·s²) atmosphere (atm): 1 atm ≡ 101.325 kPa = 760 Torr bar (bar): 1 bar ≡ 1e6 dyn/cm² ≡ 0.1 MPa barye (Ba): 1 Ba ≡ 1 dyn/cm² ≡ 0.1 Pa pounds per square inch (psi): 1 psi ≡ 1 lbm/in² = 6.894757293 kPa thousand pounds per square inch (ksi): 1 ksi ≡ 1000psi = 6.894757293 MPa Torr (Torr): 760 Torr = 1 atm = 101.325 kPa
Energy SI Unit: joule (J), defined as N·m = kg·m²/s². British thermal unit (Btu): 1 Btu ≈ 1.054kJ (definitions vary) calorie (cal): 1 cal ≡ 4.184 J (thermochemical; other calories exist) Calorie (Cal): 1 Cal ≡ 1 kcal ≡ 4.184kJ (thermochemical) electron-volt (eV): 1 eV ≡ 1 V·e = 1.60217653e-19 J (uncertainty 14) erg (erg): 1 erg ≡ 1 g·cm/s² ≡ 1e-7 J foe (foe): 1 foe ≡ 1e51 erg ≡ 1e44 J foot-pounds (ft·lbf): 1 ft·lbf ≡ 1.3558179483314004J watt-hour (Wh): 1 Wh ≡ 3600 J
Power SI Unit: watt (W), defined as J/s = kg·m²/s³. ergs per second (erg/s): 1 erg/s ≡ 1e-7 W foot-pounds per second (ft·lbf/s): 1 ft·lbf/s = 1.3558179483314004 W horsepower (hp): 1 hp ≡ 550 ft·lbf/s ≡ 745.69987158227022 W (mechanical) relativistic limit: c⁵/(4G) = 9.0708e51 W, uncertainty 1
Electric Current and Field SI Unit: ampere (A) coulomb (C): 1 C ≡ 1 A·s electrostatic unit (esu): 1 esu ≡ 1/(2997924580) C = 3.33564095198152e-10 C [stat-coulomb (statC), franklin (Fr)] elementary charge (e): 1 e = 1.60217653e-19 C, uncertainty 14 farad (F): 1 F ≡ 1 C/V ≡ 1 s⁴·A²/(m²·kg) ohm (Ω): 1 Ω ≡ 1 V/A ≡ 1 m²·kg/(s³·A²) statvolt (statV): 1 statV ≡ 1 erg/esu ≡ 299.792458 V volt (V): 1 V ≡ 1 J/C ≡ 1 W/A ≡ 1 m²·kg/(A·s³)
Magnetic Field SI Unit tesla (T) permeability of free space (μ_0): μ_0 ≡ 4π/10^7
Area SI Unit: square meter, m² square centimeter (cm²): 1 cm² ≡ 1e-4 m² square inch (in²): 1 in² ≡ 6.4516 cm² ≡ 6.4516e-4 m² square foot (ft²): 1 ft² ≡ 144 in² ≡ 0.09290304 m² square mile (mi²): 1 mi² ≡ 2.589988110336 km² ≡ 2.589988110336e6 m² hectare (ha): 1 ha ≡ 1e-2 km² ≡ 1e4 m²
Volume SI Unit: cubic meter, m³ cubic centimeter (cm³): 1 cm³ ≡ 1 mL ≡ 1e-6 m³ cubic inch (in³): 1 in³ ≡ 16.387064 cm³ liter (L): 1 L ≡ 1 dm³ ≡ 0.001 m³
Velocity SI Unit: meters per second, m/s speed of light: c ≡ 299792458m/s kilometer per hour(km/h)-->1km/h = 0.278m/s
Acceleration SI Unit: meter per second squared, m/s² feet per second squared (ft/s²): 1 ft/s² ≡ 0.3048 m/s² standard gravity: 1 gee ≡ 9.80665 m/s² = 32.1740486 ft/s²
Density kiolometers per cubic meter (kg/m³)
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Posted: Thu Jun 15, 2006 7:57 pm
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Posted: Fri Jun 16, 2006 10:43 am
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Posted: Fri Jun 16, 2006 11:16 am
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Posted: Fri Jun 16, 2006 7:36 pm
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Posted: Fri Jun 16, 2006 7:45 pm
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Posted: Sat Jun 17, 2006 8:02 am
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Posted: Sat Jun 17, 2006 9:14 am
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Posted: Sat Jun 17, 2006 5:20 pm
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Some notes: 1. These are more properly called initialisms rather than acronyms, although that's a bit of a pedantic point that almost nobody would actually care about. 2. EM is a common shorthand for electromagnetism or electromagnetic. 3. The Celsius scale has a 273.15 unit difference with kelvin, rather than 273.16. 4. Unlike all other SI units, the base units for mass is the suffixed unit kilogram rather than the expected gram. 5. Why bother listing the suffixed units like the millimeter or megapascal? The suffixes are already given. Instead, there are other units not listed that are still used in physics. For example, the cgs system is still popular in electromagnetism, with its dynes, ergs, etc. 6. Some coverage of U.S. customary units may be a good thing, since some of them are very much in use in engineering fields. For example, measuring strength of materials in terms of pounds per square inch (psi) or kilopsi (ksi) is fairly common in materials science and engineering.
If you have no objections to this, I can simply make those changes myself (except probably #1). I would have done so already, but it would be bad form without asking first.
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Posted: Sat Jun 17, 2006 5:41 pm
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Posted: Sat Jun 17, 2006 7:33 pm
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VorpalNeko Some notes: 1. These are more properly called initialisms rather than acronyms, although that's a bit of a pedantic point that almost nobody would actually care about. I didn't really call them anything
VorpalNeko 2. EM is a common shorthand for electromagnetism or electromagnetic. 3. The Celsius scale has a 273.15 unit difference with kelvin, rather than 273.16.
off by 0.01 ~ that's hilarious.
VorpalNeko 4. Unlike all other SI units, the base units for mass is the suffixed unit kilogram rather than the expected gram. I started that way, but then decided it would be more repetitive if I went by order of magnitude (cause I was writing it up one by one so I didn't wanna put any brainpower into it). You can change them hwr, go ahead, do whatever you want with it, kill yourself, I already spent too much time on writing it up. It's not really written in stone, it's meant to be improved.
VorpalNeko 5. Why bother listing the suffixed units like the millimeter or megapascal? The suffixes are already given. Instead, there are other units not listed that are still used in physics. For example, the cgs system is still popular in electromagnetism, with its dynes, ergs, etc. I dunno, I was being a**l, change it.
VorpalNeko 6. Some coverage of U.S. customary units may be a good thing, since some of them are very much in use in engineering fields. For example, measuring strength of materials in terms of pounds per square inch (psi) or kilopsi (ksi) is fairly common in materials science and engineering.
good idea, that should be in there.
VorpalNeko If you have no objections to this, I can simply make those changes myself (except probably #1). I would have done so already, but it would be bad form without asking first.
I have no objections.
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Posted: Sun Jun 18, 2006 12:20 am
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Posted: Sun Jun 18, 2006 4:52 pm
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Posted: Tue Jun 20, 2006 7:45 pm
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