Appendix A Useful Information – Constants, Units, Formulae
This appendix is broken into several tables.
- Table 3, Important Constants
- Table 4, Submicroscopic Masses
- Table 5, Solar System Data
- Table 6, Metric Prefixes for Powers of Ten and Their Symbols
- Table 7, The Greek Alphabet
- Table 8, SI units
- Table 9, Selected British Units
- Table 10, Other Units
- Table 11, Useful Formulae
Table 3. Important Constants1
| Symbol | Meaning | Best Value | Approximate Value |
|---|---|---|---|
| $latex c $ | Speed of light in vacuum | $latex 2.99792458 \times 10^8 \text{m/s} $ | $latex 3.00 \times 10^8 \text{m/s}$ |
| $latex G $ | Gravitational constant | $latex 6.67408(31) \times 10^{-11} \;\text{N} \cdot \text{m}^2 / \text{kg}^2 $ | $latex 6.67 \times 10^{-11} \;\text{N} \cdot \text{m}^2 / \text{kg}^2 $ |
| $latex N_A$ | Avogadro’s number | $latex 6.02214129(27) \times 10^{23}$ | $latex 6.02 \times 10^{23} $ |
| $latex k $ | Boltzmann’s constant | $latex 1.3806488(13) \times 10^{-23} \;\text{J} / \text{K}$ | $latex 1.38 \times 10^{-23} \;\text{J} / \text{K}$ |
| $latex R $ | Gas constant | $latex 8.3144621(75) \;\text{J} / \text{mol} \cdot \text{K}$ | $latex 8.31 \;\text{J} / \text{mol} \cdot \text{K} = 1.99 \text{cal} / \text{mol} \cdot \text{K} = 0.0821 \text{atm} \cdot \text{L} / \text{mol} \cdot \text{K}$ |
| $latex \sigma $ | Stefan-Boltzmann constant | $latex 5.670373(21) \times 10^{-8} \;\text{W} / \text{m}^2 \cdot \text{K}$ | $latex 5.67 \times 10^{-8} \;\text{W} / \text{m}^2 \cdot \text{K}$ |
| $latex k $ | Coulomb force constant | $latex 8.987551788 \dots \times 10^9 \;\text{N} \cdot \text{m}^2 / \text{C}^2$ | $latex 8.99 \times 10^9 \;\text{N} \cdot \text{m}^2 / \text{C}^2$ |
| $latex q_e$ | Charge on electron | $latex -1.602176565(35) \times 10^{-19} \;\text{C}$ | $latex -1.60 \times 10^{-19} \;\text{C}$ |
| $latex \varepsilon _0$ | Permittivity of free space | $latex 8.854187817 \dots \times 10^{-12} \;\text{C}^2 / \text{N} \cdot \text{m}^2 $ | $latex 8.85 \dots \times 10^{-12} \;\text{C}^2 / \text{N} \text{m}^2 $ |
| $latex \mu _0 $ | Permeability of free space | $latex 4 \pi \times 10^{-7} \;\text{T} \cdot \;\text{m}/ \text{A}$ | $latex 1.26 \times 10^{-6} \;\text{T} \cdot \text{m} / \text{A}$ |
| $latex h $ | Planck’s constant | $latex 6.62606957(29) \times 10^{-34} \;\text{J} \cdot \text{s}$ | $latex 6.63 \times 10^{-34} \;\text{J} \cdot \text{s}$ |
| Symbol | Meaning | Best Value | Approximate Value |
|---|---|---|---|
| $latex m_e$ | Electron mass | $latex 9.10938291(40) \times 10^{-31} \text{kg} $ | $latex 9.11 \times 10^{-31} \text{kg} $ |
| $latex m_p $ | Proton mass | $latex 1.672621777(74) \times 10^{-27} \text{kg} $ | $latex 1.6726 \times 10^{-27} \text{kg} $ |
| $latex m_n $ | Neutron mass | $latex 1.674927351(74) \times 10^{-27} \text{kg} $ | $latex 1.6749 \times 10^{-27} \text{kg} $ |
| $latex \text{u} $ | Atomic mass unit | $latex 1.660538921(73) \times 10^{-27} \text{kg} $ | $latex 1.6605 \times 10^{-27} \text{kg} $ |
| Table 4. Submicroscopic Masses2 | |||
| Sun | mass | $latex 1.99 \times 10^{30} \text{kg} $ |
| average radius | $latex 6.96 \times 10^8 \text{m}$ | |
| Earth-sun distance (average) | $latex 1.496 \times 10^{11} \text{m} $ | |
| Earth | mass | $latex 5.9736 \times 10^{24} \text{kg} $ |
| average radius | $latex 6.376 \times 10^6 \text{m}$ | |
| orbital period | $latex 3.16 \times 10^7 \text{s} $ | |
| Moon | mass | $latex 7.35 \times 10^{22} \text{kg} $ |
| average radius | $latex 1.74 \times 10^6 \text{m} $ | |
| orbital period (average) | $latex 2.36 \times 10^6 \text{s} $ | |
| Earth-moon distance (average) | $latex 3.84 \times 10^8 \text{m} $ | |
| Table 5. Solar System Data | ||
| Prefix | Symbol | Value | Prefix | Symbol | Value |
|---|---|---|---|---|---|
| tera | T | $latex 10^{12}$ | deci | d | $latex 10^{-1}$ |
| giga | G | $latex 10^{9}$ | centi | c | $latex 10^{-2}$ |
| mega | M | $latex 10^{6}$ | milli | m | $latex 10^{-3}$ |
| kilo | k | $latex 10^{3}$ | micro | $latex \mu $ | $latex 10^{-6}$ |
| hecto | h | $latex 10^{2}$ | nano | n | $latex 10^{-9}$ |
| deka | da | $latex 10^{1}$ | pico | p | $latex 10^{-12}$ |
| — | — | $latex 10^{0} (= 1)$ | femto | f | $latex 10^{-15}$ |
| Table 6. Metric Prefixes for Powers of Ten and Their Symbols | |||||
| Alpha | A | $latex \alpha $ | Eta | Η | $latex \eta $ | Nu | Ν | $latex \nu $ | Tau | Τ | $latex \tau $ |
| Beta | Β | $latex \beta $ | Theta | Θ | $latex \theta $ | Xi | Ξ | $latex \xi $ | Upsilon | Υ | $latex \upsilon $ |
| Gamma | Γ | $latex \gamma $ | Iota | Ι | $latex \iota $ | Omicron | Ο | $latex \o $ | Phi | Φ | $latex \phi $ |
| Delta | Δ | $latex \delta $ | Kappa | Κ | $latex \kappa $ | Pi | Π | $latex \pi $ | Chi | Χ | $latex \chi $ |
| Epsilon | Ε | $latex \epsilon $ | Lambda | Λ | $latex \lambda $ | Rho | Ρ | $latex \rho $ | Psi | Ψ | $latex \psi $ |
| Zeta | Ζ | $latex \zeta $ | Mu | Μ | $latex \mu $ | Sigma | Σ | $latex \sigma $ | Omega | Ω | $latex \omega $ |
| Table 7. The Greek Alphabet | |||||||||||
| Entity | Abbreviation | Name | |
|---|---|---|---|
| Fundamental units | Length | $latex \text{m} $ | meter |
| Mass | $latex \text{kg} $ | kilogram | |
| Time | $latex \text{s} $ | second | |
| Current | $latex \text{A} $ | ampere | |
| Supplementary unit | Angle | $latex \text{rad}$ | radian |
| Derived units | Force | $latex \text{N} = \text{kg} \cdot \text{m} / \text{s}^2 $ | newton |
| Energy | $latex \text{J} = \text{kg} \cdot \text{m}^2 / \text{s}^2 $ | joule | |
| Power | $latex \text{W} = \text{J} / \text{s}$ | watt | |
| Pressure | $latex \text{Pa} = \text{N} / \text{m}^2 $ | pascal | |
| Frequency | $latex \text{Hz} = 1/ \text{s} $ | hertz | |
| Electronic potential | $latex \text{V} = \text{J} / \text{C}$ | volt | |
| Capacitance | $latex \text{F} = \text{C} / \text{V}$ | farad | |
| Charge | $latex \text{C} = \text{s} \cdot \text{A}$ | coulomb | |
| Resistance | $latex \Omega = \text{V} / \text{A}$ | ohm | |
| Magnetic field | $latex \text{T} = \text{N} / (\text{A} \cdot \text{m}) $ | tesla | |
| Nuclear decay rate | $latex \text{Bq} = 1 / \text{s}$ | becquerel | |
| Table 8. SI Units | |||
| Length | $latex 1 \;\text{inch} \; (\text{in.}) = 2.54 \;\text{cm} \; (\text{exactly}) $ |
| $latex 1 \;\text{foot} \; (\text{ft}) = 0.3048 \;\text{m} $ | |
| $latex 1 \;\text{mile} \; (\text{mi}) = 1.609 \;\text{km} $ | |
| Force | $latex 1 \;\text{pound} \; (\text{lb}) = 4.448 \;\text{N} $ |
| Energy | $latex 1 \;\text{British thermal unit} \; (\text{Btu}) = 1.055 \times 10^3 \text{J}$ |
| Power | $latex 1 \;\text{horsepower} \; (\text{hp}) = 746 \;\text{W}$ |
| Pressure | $latex 1 \;\text{lb} / \text{in}^2 = 6.895 \times 10^3 \;\text{Pa}$ |
| Table 9. Selected British Units | |
| Length | $latex 1 \;\text{light year} \; (\text{ly}) = 9.46 \times 10^{15} \; \text{m}$ |
| $latex 1 \; \text{astronomical unit} \;(\text{au}) = 1.50 \times 10^{11} \; \text{m}$ | |
| $latex 1 \;\text{nautical mile} = 1.852 \;\text{km}$ | |
| $latex 1 \;\text{angstrom} ( \AA ) = 10^{-10} \text{m}$ | |
| Area | $latex 1 \;\text{acre} \;(\text{ac}) = 4.05 \times 10^3 \text{m}^2$ |
| $latex 1 \;\text{square foot} \; (\text{ft}^2) = 9.29 \times 10^{-2} \;\text{m}^2 $ | |
| $latex 1 \;\text{barn} \;(b) = 10^{-28} \;\text{m}^2 $ | |
| Volume | $latex 1 \;\text{liter} \;(L) = 10^{-3} \; \text{m}^3 $ |
| $latex 1 \;\text{U.S. gallon} \;(\text{gal}) = 3.785 \times 10^{-3} \;\text{m}^3 $ | |
| Mass | $latex 1 \;\text{solar mass} = 1.99 \times 10^{30} \; \text{kg}$ |
| $latex 1 \;\text{metric ton} = 10^3 \;\text{kg}$ | |
| $latex 1 \;\text{atomic mass unit} \;(u)= 1.6605 \times 10^{-27} \;\text{kg}$ | |
| Time | $latex 1 \;\text{year} \;(\text{y}) = 3.16 \times 10^7 \;\text{s}$ |
| $latex 1 \;\text{day} \;(\text{d}) = 86,400 \;\text{s}$ | |
| Speed | $latex 1 \;\text{mile per hour} \;(\text{mph}) = 1.609 \;\text{km} / \text{h} $ |
| $latex 1 \;\text{nautical mile per hour} \;(\text{naut}) = 1.852 \;\text{km} / \text{h}$ | |
| Angle | $latex 1 \;\text{degree} \;(^{\circ}) = 1.745 \times 10^{-2} \;\text{rad} $ |
| $latex 1 \;\text{minute of arc} \; ($’ $latex ) = 1/60 \;\text{degree} $ | |
| $latex 1 \;\text{second of arc} \; (“) = 1/60 \;\text{minute of arc} $ | |
| $latex 1 \;\text{grad} = 1.571 \times 10^{-2} \;\text{rad} $ | |
| Energy | $latex 1 \;\text{kiloton TNT} \;(\text{kT}) = 4.2 \times 10^{12} \;\text{J} $ |
| $latex 1 \; \text{kilowatt hour} \;(\text{kW} \cdot h) = 3.60 \times 10^6 \;\text{J}$ | |
| $latex 1 \;\text{food calorie} \;(\text{kcal}) = 4186 \;\text{J} $ | |
| $latex 1 \;\text{calorie} \;(\text{cal}) = 4.186 \;\text{J}$ | |
| $latex 1 \;\text{electron volt} \;(\text{eV}) = 1.60 \times 10^{-19} \;\text{J}$ | |
| Pressure | $latex 1 \;\text{atmosphere} \;(\text{atm}) = 1.013 \times 10^5 \;\text{Pa}$ |
| $latex 1 \;\text{millimeter of mercury} \;(\text{mm Hg}) = 133.3 \;\text{Pa}$ | |
| $latex 1 \;\text{torricelli} \;(\text{torr}) = 1 \;\text{mm Hg} = 133.3 \;\text{Pa}$ | |
| Nuclear decay rate | $latex 1 \;\text{curie} \;(\text{Ci}) = 3.70 \times 10^{10} \; \text{Bq}$ |
| Table 10. Other Units | |
| $latex \text{Circumference of a circle with radius} \; \text{r} \; \text{or diameter} \;\text{d}$ | $latex C = 2 \pi r = \pi d $ |
| $latex \text{Area of a circle with radius} \; r \;\text{or diameter} d $ | $latex A = \pi r^2 = \pi d^{2}/4 $ |
| $latex \text{Area of a sphere with radius} \; r $ | $latex A = 4 \pi r^2 $ |
| $latex \text{Volume of a sphere with radius} \; r $ | $latex V = (4/3)( \pi r^3) $ |
| Table 11. Useful Formulae | |
| Units of Length | |||
|---|---|---|---|
| meter (m) | = 39.37 inches (in.)
= 1.094 yards (yd)
|
angstrom (Å) | = 10–8 cm (exact, definition)
= 10–10 m (exact, definition)
|
| centimeter (cm) | = 0.01 m (exact, definition) | yard (yd) | = 0.9144 m |
| millimeter (mm) | = 0.001 m (exact, definition) | inch (in.) | = 2.54 cm (exact, definition) |
| kilometer (km) | = 1000 m (exact, definition) | mile (US) | = 1.60934 km |
| Units of Volume | |||
|---|---|---|---|
| liter (L) | = 0.001 m3 (exact, definition)
= 1000 cm3 (exact, definition)
= 1.057 (US) quarts
|
liquid quart (US) | = 32 (US) liquid ounces (exact, definition)
= 0.25 (US) gallon (exact, definition)
= 0.9463 L
|
| milliliter (mL) | = 0.001 L (exact, definition)
= 1 cm3 (exact, definition)
|
dry quart | = 1.1012 L |
| microliter (μL)(μL) | = 10–6 L (exact, definition)
= 10–3 cm3 (exact, definition)
|
cubic foot (US) | = 28.316 L |
| Units of Mass | |||
|---|---|---|---|
| gram (g) | = 0.001 kg (exact, definition) | ounce (oz) (avoirdupois) | = 28.35 g |
| milligram (mg) | = 0.001 g (exact, definition) | pound (lb) (avoirdupois) | = 0.4535924 kg |
| kilogram (kg) | = 1000 g (exact, definition)
= 2.205 lb
|
ton (short) | =2000 lb (exact, definition)
= 907.185 kg
|
| ton (metric) | =1000 kg (exact, definition)
= 2204.62 lb
|
ton (long) | = 2240 lb (exact, definition)
= 1.016 metric ton
|
| Units of Energy | |
|---|---|
| 4.184 joule (J) | = 1 thermochemical calorie (cal) |
| 1 thermochemical calorie (cal) | = 4.184 × 107 erg |
| erg | = 10–7 J (exact, definition) |
| electron-volt (eV) | = 1.60218 × 10−19 J = 23.061 kcal mol−1 |
| liter∙atmosphere | = 24.217 cal = 101.325 J (exact, definition) |
| nutritional calorie (Cal) | = 1000 cal (exact, definition) = 4184 J |
| British thermal unit (BTU) | = 1054.804 J BTU is the amount of energy needed to heat one pound of water by one degree Fahrenheit. Therefore, the exact relationship of BTU to joules and other energy units depends on the temperature at which BTU is measured. 59 °F (15 °C) is the most widely used reference temperature for BTU definition in the United States. At this temperature, the conversion factor is the one provided in this table. |
Footnotes
- 1 Stated values are according to the National Institute of Standards and Technology Reference on Constants, Units, and Uncertainty, www.physics.nist.gov/cuu (accessed May 18, 2012). Values in parentheses are the uncertainties in the last digits. Numbers without uncertainties are exact as defined.
- 2 Stated values are according to the National Institute of Standards and Technology Reference on Constants, Units, and Uncertainty, www.physics.nist.gov/cuu (accessed May 18, 2012). Values in parentheses are the uncertainties in the last digits. Numbers without uncertainties are exact as defined.
