Measurements by keara

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									          Measurements
            SI           Common
Mass     kilogram (Kg)   gram (g)
Length   meter (m)       centimeter (cm)
Time     second (s)      second (s)
Temp.    Kelvin (K)      Celsius (0C)
•   Kilo = 1000, (k), 103
•   centi = 100, (c), 102
•   Micro = 1/1,000,000 = 10-6 (µ)
•   1g = 1,000,000µg = 106g
•   1cm = 10-2m
•   1m = 100cm
•   Nano = 10-9
•   1 sec = 109ns
    Examples of Independent Units
•   Table 1. SI base units SI base unit
•   Base quantity             Name     Symbol
•   length                    meter    m
•   mass                      kilogram kg
•   time                      second    s
•   electric current          ampere   A
•   thermodynamic temperature kelvin   K
•   amount of substance       mole     mol
•   luminous intensity        candela  cd
          Examples of derived units
• Table 2. Examples of SI derived units SI derived unit
• Derived quantity                  Name                                     Symbol
• area                              square meter                             m2
• volume                            cubic meter                              m3
• speed, velocity                   meter per second                         m/s
• acceleration                      meter per second squared                m/s2
• wave number                       reciprocal meter                        m-1
•  mass density                     kilogram per cubic meter                kg/m3
• specific volume                   cubic meter per kilogram                m3/kg
• current density                   ampere per square meter                 A/m2
• magnetic field strength           ampere per meter                        A/m
• amount-of-substance concentration mole per cubic meter                    mol/m3
• luminance                         candela per square meter                cd/m2
• mass fraction                     kilogram per kilogram,
                                  which may be represented by the number 1 kg/kg = 1
    Independent units you should know
•   Mass
•   Quantity of matter
•   Constant regardless of position
•   Occupies space
•   Measured with a balance –actually comparing
    masses
•   Weight
•   Effect of gravity on mass
•   Changes with position
•   Measured with a scale
• Temperature
• Measure of the hotness of an object
• Man made
• Measured with thermometer (0C)
• Heat is energy that is detected only when it flows from
  high to low temp., naturally occurring (always flows
  from high to low temp.)
• Boiling = 1000C, Freezing = 00C
• Absolute 0 = lowest temperature that can exist in the
  Universe 0C = -273.150C
• Kelvin (K) = absolute 0 =0C = 273.15
    Derived Units = dependant that you
              should know
•                         SI      Common
• Volume = l x w x h = m3 cm3 (cubic centimeter, cc)
• Density = mass/volume kg/m3 g/cm3
  -chapter 17 in your book




• Example of volume
• 8.42cm x 5.749cm x 3.6cm = 174.26cm3 = 170cm3 =
  1.7 x 102cm3 two significant digits
• Example of Density
• A fish tank measuring 14.3cm x 73.0cm x
  .72cm is filled with olive oil that has a mass of
  8.2 x 103g. What is the density of the olive oil
  in g/cm3

								
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