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Chapter 17: Useful Information

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    46261
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    This appendix is broken into several tables.

    • Table \(\PageIndex{1}\), Important Constants
    • Table \(\PageIndex{2}\), Submicroscopic Masses
    • Table \(\PageIndex{3}\), Solar System Data
    • Table \(\PageIndex{4}\), Metric Prefixes for Powers of Ten and Their Symbols
    • Table \(\PageIndex{5}\), The Greek Alphabet
    • Table \(\PageIndex{6}\), SI units
    • Table \(\PageIndex{7}\), Selected British Units
    • Table \(\PageIndex{8}\), Other Units
    • Table \(\PageIndex{9}\), Useful Formulae
    Table \(\PageIndex{1}\): Important Constants1
    Symbol Meaning Best Value Approximate Value

    \(c\)

    Speed of light in vacuum \(2.99792458 \times 10^{8} \mathrm{~m} / \mathrm{s}\) \(3.00 \times 10^{8} \mathrm{~m} / \mathrm{s}\)

    \(G\)

    Gravitational constant \(6.67430(15) \times 10^{-11} \mathrm{~N} \cdot \mathrm{m}^{2} / \mathrm{kg}^{2}\) \(6.67 \times 10^{-11} \mathrm{~N} \cdot \mathrm{m}^{2} / \mathrm{kg}^{2}\)

    \(N_{A}\)

    Avogadro’s number \(6.02214076 \times 10^{23}\) \(6.02 \times 10^{23}\)

    \(k\)

    Boltzmann’s constant \(1.380649 \times 10^{-23} \mathrm{~J} / \mathrm{K}\) \(1.38 \times 10^{-23} \mathrm{~J} / \mathrm{K}\)

    \(R\)

    Gas constant \(8.314462618 \mathrm{~J} / \mathrm{mol} \cdot \mathrm{K}\) \(8.31 \mathrm{~J} / \mathrm{mol} \cdot \mathrm{K}\)

    \(\sigma\)

    Stefan-Boltzmann constant \(5.670374419 \times 10^{-8} \mathrm{~W} / \mathrm{m}^{2} \cdot \mathrm{K}\) \(5.67 \times 10^{-8} \mathrm{~W} / \mathrm{m}^{2} \cdot \mathrm{K}\)

    \(k\)

    Coulomb force constant \(8.9875517923(13) \times 10^{9} \mathrm{~N} \cdot \mathrm{m}^{2} / \mathrm{C}^{2}\) \(8.99 \times 10^{9} \mathrm{~N} \cdot \mathrm{m}^{2} / \mathrm{C}^{2}\)

    \(e\)

    Elementary charge \(1.602176634 \times 10^{-19} \mathrm{C}\) \(1.60 \times 10^{-19} \mathrm{C}\)

    \(\varepsilon_{0}\)

    Permittivity of free space \(8.8541878128(13) \times 10^{-12} \mathrm{C}^{2} / \mathrm{N} \cdot \mathrm{m}^{2}\) \(8.85 \times 10^{-12} \mathrm{C}^{2} / \mathrm{N} \cdot \mathrm{m}^{2}\)

    \(\mu_{0}\)

    Permeability of free space \(4 \pi \times 10^{-7} \mathrm{~T} \cdot \mathrm{m} / \mathrm{A}\) \(1.26 \times 10^{-6} \mathrm{~T} \cdot \mathrm{m} / \mathrm{A}\)

    \(h\)

    Planck’s constant \(6.62607015 \times 10^{-34} \mathrm{~J} \cdot \mathrm{s}\) \(6.63 \times 10^{-34} \mathrm{~J} \cdot \mathrm{s}\)
    Table \(\PageIndex{2}\): Submicroscopic Masses2
    Symbol Meaning Best Value Approximate Value

    \(m_{e}\)

    Electron mass \(9.1093837015(28) \times 10^{-31} \mathrm{~kg}\) \(9.11 \times 10^{-31} \mathrm{~kg}\)

    \(m_{p}\)

    Proton mass \(1.67262192369(51) \times 10^{-27} \mathrm{~kg}\) \(1.67 \times 10^{-27} \mathrm{~kg}\)

    \(m_{n}\)

    Neutron mass \(1.67492749804(95) \times 10^{-27} \mathrm{~kg}\) \(1.67 \times 10^{-27} \mathrm{~kg}\)

    \(u\)

    Atomic mass unit \(1.66053906660(50) \times 10^{-27} \mathrm{~kg}\) \(1.66 \times 10^{-27} \mathrm{~kg}\)
    Table \(\PageIndex{3}\): Solar System Data
    Sun mass

    \(1.99 \times 10^{30} \mathrm{~kg}\)

    average radius

    \(6.96 \times 10^{8} \mathrm{~m}\)

    Earth-sun distance (average)

    \(1.496 \times 10^{11} \mathrm{~m}\)

    Earth mass

    \(5.9736 \times 10^{24} \mathrm{~kg}\)

    average radius

    \(6.376 \times 10^{6} \mathrm{~m}\)

    orbital period

    \(3.16 \times 10^{7} \mathrm{~s}\)

    Moon mass

    \(7.35 \times 10^{22} \mathrm{~kg}\)

    average radius

    \(1.74 \times 10^{6} \mathrm{~m}\)

    orbital period (average)

    \(2.36 \times 10^{6} \mathrm{~s}\)

    Earth-moon distance (average)

    \(3.84 \times 10^{8} \mathrm{~m}\)

    Table \(\PageIndex{4}\): Metric Prefixes for Powers of Ten and Their Symbols
    Prefix Symbol Value Prefix Symbol Value
    tera T \(10^{12}\) deci d \(10^{-1}\)
    giga G \(10^{9}\) centi c \(10^{-2}\)
    mega M \(10^{6}\) milli m \(10^{-3}\)
    kilo k \(10^{3}\) micro

    \(\mu\)

    \(10^{-6}\)
    hecto h \(10^{2}\) nano n \(10^{-9}\)
    deka da \(10^{1}\) pico p \(10^{-12}\)
    \(10^{\circ}(=1)\) femto f \(10^{-15}\)
    Table \(\PageIndex{5}\): The Greek Alphabet
    Alpha \(\text { A }\) \(\alpha\) Eta \(\mathrm{H}\) \(\eta\) Nu \(N\) \(\nu\) Tau \(\mathrm{T}\) \(\tau\)
    Beta \(\text { B }\) \(\beta\) Theta \(\Theta\) \(\theta\) Xi \(\Xi\) \(\xi\) Upsilon \(\Upsilon\) \(v\)
    Gamma \(\Gamma\) \(\gamma\) Iota \(\mathrm{I}\) \(\iota\) Omicron \(\mathrm{O}\) \(o\) Phi \(\Phi\) \(\phi\)
    Delta \(\Delta\) \(\delta\) Kappa \(\mathrm{K}\) \(\kappa\) Pi \(\Pi\) \(\pi\) Chi \(\mathrm{X}\) \(\chi\)
    Epsilon \(\mathrm{E}\) \(\varepsilon\) Lambda \(\Lambda\) \(\lambda\) Rho \(\mathrm{P}\) \(\rho\) Psi \(\Psi\) \(\psi\)
    Zeta \(\text { Z }\) \(\zeta\) Mu \(\mathrm{M}\) \(\mu\) Sigma \(\Sigma\) \(\sigma\) Omega \(\Omega\) \(\omega\)
    Table \(\PageIndex{6}\): SI Units
      Entity Abbreviation Name
    Fundamental units Length m meter
    Mass kg kilogram
    Time s second
    Current A ampere
    Supplementary unit Angle rad radian
    Derived units Force

    \(\mathrm{N}=\mathrm{kg} \cdot \mathrm{m} / \mathrm{s}^{2}\)

    newton
    Energy

    \(\mathrm{J}=\mathrm{kg} \cdot \mathrm{m}^{2} / \mathrm{s}^{2}\)

    joule
    Power

    \(\mathrm{W}=\mathrm{J} / \mathrm{s}\)

    watt
    Pressure

    \(\mathrm{Pa}=\mathrm{N} / \mathrm{m}^{2}\)

    pascal
    Frequency

    \(\mathrm{Hz}=1 / \mathrm{s}\)

    hertz
    Electronic potential

    \(\mathrm{V}=\mathrm{J} / \mathrm{C}\)

    volt
    Capacitance

    \(\mathrm{F}=\mathrm{C} / \mathrm{V}\)

    farad
    Charge

    \(\mathrm{C}=\mathrm{s} \cdot \mathrm{A}\)

    coulomb
    Resistance

    \(\Omega=\mathrm{V} / \mathrm{A}\)

    ohm
    Magnetic field

    \(\mathrm{T}=\mathrm{N} /(\mathrm{A} \cdot \mathrm{m})\)

    tesla
    Nuclear decay rate

    \(\mathrm{Bq}=1 / \mathrm{s}\)

    becquerel
    Table \(\PageIndex{7}\): Selected British Units
    Length \(1 \text { inch }(\text { in })=2.54 \mathrm{~cm} \text { (exactly) }\)
    \(1 \text { foot }(\mathrm{ft})=12 \text { in }=0.3048 \mathrm{~m}\)
    \(1 \operatorname{yard}(\mathrm{y d})=3 \mathrm{ft}=0.9144 \mathrm{~m}\)
    \(1 \text { mile }(\mathrm{mi})=1760 \mathrm{yd}=1.609 \mathrm{~km}\)
    Force \(1 \text { pound }(\mathrm{lb})=4.448 \mathrm{~N}\)
    Energy \(1 \text { British thermal unit }(\mathrm{Btu})=1.055 \times 10^{3} \mathrm{~J}\)
    Power \(1 \text { horsepower }(\mathrm{hp})=746 \mathrm{~W}\)
    Pressure \(1 \mathrm{lb} / \mathrm{in}^{2}=6.895 \times 10^{3} \mathrm{~Pa}\)
    Table \(\PageIndex{8}\): Other Units
    Length \(1 \text { light year }(\text {ly})=9.46 \times 10^{15} \mathrm{~m}\)
    \(1 \text { astronomical unit }(\mathrm{au})=1.50 \times 10^{11} \mathrm{~m}\)
    \(1 \text { nautical mile }=1.852 \mathrm{~km}\)
    \(1 \text { angstrom }(Å)=10^{-10} \mathrm{~m}\)
    Area \(1 \text { acre }(\mathrm{ac})=4.05 \times 10^{3} \mathrm{~m}^{2}\)
    \(1 \text { square foot }\left(\mathrm{ft}^{2}\right)=9.29 \times 10^{-2} \mathrm{~m}^{2}\)
    \(1 \operatorname{barn}(b)=10^{-28} \mathrm{~m}^{2}\)
    Volume \(1 \text { liter }(L)=10^{-3} \mathrm{~m}^{3}\)
    \(1 \text { U.S. gallon (gal) }=3.785 \times 10^{-3} \mathrm{~m}^{3}\)
    Mass \(1 \text { solar mass }=1.99 \times 10^{30} \mathrm{~kg}\)
    \(1 \text { metric ton }=10^{3} \mathrm{~kg}\)
    \(1 \text { atomic mass unit }(u)=1.6605 \times 10^{-27} \mathrm{~kg}\)
    Time \(1 \operatorname{year} \ (y)=3.16 \times 10^{7} \mathrm{~s}\)
    \(1 \text { day }(d)=86,400 \mathrm{~s}\)
    Speed \(1 \text { mile per hour }(\mathrm{mph})=1.609 \mathrm{~km} / \mathrm{h}\)
    \(1 \text { nautical mile per hour (naut) }=1.852 \mathrm{~km} / \mathrm{h}\)
    Angle \(1 \text { degree }\left(^{\circ}\right)=1.745 \times 10^{-2} \mathrm{~rad}\)
    \(1 \text { minute of arc }\left(^{\prime}\right)=1 / 60 \text { degree }\)
    \(1 \text { second of arc }(")=1 / 60 \text { minute of arc }\)
    \(1 \mathrm{~grad~}=1.571 \times 10^{-2} \mathrm{~rad}\)
    Energy \(1 \text { kiloton TNT }(\mathrm{kT})=4.2 \times 10^{12} \mathrm{~J}\)
    \(1 \text { kilowatt hour }(\mathrm{kW} \cdot h)=3.60 \times 10^{6} \mathrm{~J}\)
    \(1 \text { food calorie }(\mathrm{kcal})=4186 \mathrm{~J}\)
    \(1 \text { calorie }(\mathrm{cal})=4.186 \mathrm{~J}\)
    \(1 \text { electron volt }(\mathrm{eV})=1.60 \times 10^{-19} \mathrm{~J}\)
    Pressure \(1 \text { atmosphere }(\text {atm})=1.013 \times 10^{5} \mathrm{~Pa}\)
    \(1 \text { millimeter of mercury }(\mathrm{mm} \mathrm{Hg})=133.3 \mathrm{~Pa}\)
    \(1 \text { torricelli (torr) }=1 \mathrm{~mm} \mathrm{Hg}=133.3 \mathrm{~Pa}\)
    Nuclear decay rate \(1 \text { curie }(\mathrm{Ci})=3.70 \times 10^{10} \mathrm{~Bq}\)
    Table \(\PageIndex{9}\): Useful Formulae
    Circumference of a circle with radius \(r\) or diameter \(d\) \(C=2 \pi r=\pi d\)
    Area of a circle with radius \(r\) or diameter \(d\) \(A=\pi r^{2}=\pi d^{2} / 4\)
    Area of a sphere with radius \(r\) \(A=4 \pi r^{2}\)
    Volume of a sphere with radius \(r\) \(V=(4 / 3)\left(\pi r^{3}\right)\)

    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 (2018 values). 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 (2018 values). Values in parentheses are the uncertainties in the last digits. Numbers without uncertainties are exact as defined.

    This page titled Chapter 17: Useful Information is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by OpenStax.

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