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- BUG#5091 Ci

    1: \label{Physical_Units}
    2: \section*{Physical Units Accepted by LON-CAPA}
    3: The following subsections show the physical units that LON-CAPA accepts. 
    4: The symbols must be used when entering the units, for example {}``35 kg''.
    5: 
    6: Note that compound units are formed by using *, / and ^. For example, an acceleration might
    7: be in terms of ``m/s^2'' or meters per second squared. This could also be expressed as``m/s/s''.
    8: Units of Newton-meters (for torque) would be entered as ``N*m''. Parentheses may be used to guarantee
    9: the correct sense of the unit. Kilometers per Ampere-hour could be written as ``km/(A*hr)'' or
   10: ``km/A/hr'' but not ``km/A*hr''. The last option would be interpreted as kilometer times hours per Ampere.
   11: 
   12: LON-CAPA will automatically perform some conversions between units of the same dimension
   13: when units are provided for a problem.
   14: You can provide an answer of ``1.45 km'' for a distance.
   15:  If the computer expects the answer in cm, it will convert your answer before comparing
   16: against the numerical solution.
   17: 
   18: Please note that if your units are inappropriate, the computer has no way of checking
   19: the appropriateness of your answer.  If units are required, only once appropriate
   20: units are provided will the system check your numerical answer.
   21: 
   22: \subsection*{Base Units}
   23: \begin{verbatim}
   24: # name      symbol     comment
   25: 
   26: meter           m      # length
   27: kilogram        kg     # mass
   28: second          s      # time
   29: ampere          A      # electric current
   30: kelvin          K      # thermodynamic temperature
   31: mole            mol    # amount of substance
   32: candela         cd     # luminous intensity
   33: decibel         dB     # log of pressure amplitude
   34: \end{verbatim}
   35: \subsection*{Prefixes}
   36: \begin{verbatim}
   37: #   Prefix     symbol     factor
   38: 
   39: yotta            Y         10^{24}
   40: zetta            Z         10^{21}
   41: exa              E         10^{18}
   42: peta             P         10^{15}
   43: tera             T         10^{12}
   44: giga             G         10^9
   45: mega             M         10^6
   46: kilo             k         10^3
   47: hecto            h         10^2
   48: deca             D         10^1
   49: 
   50: deci             d         10^-1
   51: centi            c         10^-2
   52: milli            m         10^-3
   53: micro            u         10^-6
   54: nano             n         10^-9
   55: pico             p         10^{-12}
   56: femto            f         10^{-15}
   57: atto             a         10^{-18}
   58: zepto            z         10^{-21}
   59: yocto            y         10^{-24}
   60: \end{verbatim}
   61: \subsection*{Derived Units}
   62: \begin{verbatim}
   63: # Derived Unit
   64: # name       symbol    comment
   65: 
   66: gram            g      # mass
   67: minute          min    # time
   68: hour            hr     # time
   69: hour            h      # time
   70: day             day    # time
   71: day             days   # time
   72: year            yr     # time
   73: pound           lb     # mass
   74: ounce           oz     # mass
   75: inch            in     # length
   76: foot            ft     # length
   77: mile            mi     # length
   78: yard            yd     # length
   79: nautical_mile   n_mi   # length, nautical mile (UK)
   80: rood            rood   # area, rood
   81: acre            acre   # area, acre
   82: hertz           Hz     # frequency
   83: litre           L      # volume
   84: newton          N      # force
   85: pound_force     lbf    # force
   86: dyne            dyn    # force
   87: pascal          Pa     # pressure, stress
   88: bar             bar    # pressure
   89: mmHg            mmHg   # pressure, millimeter of mercury
   90: torr            torr   # pressure
   91: atm             atm    # standard atmosphere
   92: joule           J      # energy, work, heat
   93: electronvolt    eV     # energy
   94: calorie         cal    # energy
   95: Btu             Btu    # energy
   96: watt            W      # power, radiant flux
   97: coulomb         C      # electric charge
   98: volt            V      # electric potential, electromotive force
   99: ohm             ohm    # electric resistance, use this in /ANS
  100: ohm             ohms   # electric resistance
  101: ohm             Ohm    # electric resistance
  102: ohm             Ohms   # electric resistance
  103: mho             mho    # electric conductance
  104: mho             mhos   # electric conductance
  105: mho             Mho    # electric conductance
  106: mho             Mhos   # electric conductance
  107: siemens         S      # electric conductance
  108: farad           F      # electric capacitance
  109: tesla           T      # magnetic flux density
  110: weber           Wb     # magnetic flux
  111: henry           H      # inductance
  112: radian          rad    # plane angle
  113: degree          deg    # plane angle (Pi rad=180 deg)
  114: steradian       sr     # solid angle
  115: lumen           lm     # luminous flux
  116: lux             lx     # illuminance
  117: becquerel       Bq     # activity (radioactive)
  118: curie           Ci     # activity (radioactive)
  119: gray            Gy     # absorbed dose (of radiation)
  120: sievert         Sv     # dose equivalent (dose equivalent index)
  121: astroUnit       AU     # mean distance earth to sun
  122: celcius         degC   # multiplicatively OK
  123: farenheight     degF   # multiplicatively OK
  124: molarity        M      # chemisty
  125: amu             amu    # atomic mass unit
  126: amu             u      # atomic mass unit
  127: \end{verbatim}
  128: \subsection*{Interpretation}
  129: The coded units are interpreted in the order of basic unit, 
  130: derived unit, then prefix. For example, ``T'' will be matched against 
  131: ``tesla'' instead of considered the prefix ``T''. Another example is that 
  132: ``min'' will match
  133: ``minutes'' instead of treated  as a combination of the prefix ``m'' and units.