Notes
Slide Show
Outline
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Measurement, Units of Measurement, Derived Measurables and Power Prefixes
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Measurement – Basic Measurables
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Fundamental Measurements
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Measurement – Units for the First Three Basic Measurables
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 Measurement – Derived Measurables and Units
Other measurables, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven SI base units.
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 Measurement – Deriving Measurables Using Equations
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 Measurement – Deriving Measurables Using Equations
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 Measurement – Deriving Measurables Using Equations
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Derived Measurables examples
 
Derived Quantity SI Units

area square meter (m2)
volume cubic meter (m3)
speed/velocity - meter per second (m/s)
acceleration   - meter per second squared (m/s2)
density - kg per cubic meter (kg/m3)
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Power Prefixes
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Power Prefixes
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Prefixes: Summary
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Try converting these …
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Try these …
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Measurables - derived from equations
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Measurement – Problems
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Answers
  • 1.a.  13.5 kilograms = 13.5 thousand grams = 13,500 grams or 13.5 x 103g.
  • (also = 1.35 x 104g.)


  • 1.b.  6,500,000 meters = 6,500 thousand meters = 6,500 x 103 m or 6.5 x 106 m.


  • 1.c.  0.0000073 second = 7.3 millionth of a second = 7.3÷1,000,000 = 7.3 x 10-6 s.
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Answers (continued)

  • 1.d.  4500 kg/m3 = 4,500 thousand grams per m3 or 4,500,000 grams/m3    {UNFINISHED}


  • But every  1 m = 100 cm and                       every 1 m3 = (100 cm) 3    =  1,000,000 cm3
  • Therefore: 4,500,000 grams/m3    = 4,500,000 grams/(1,000,000 cm3) = 4.5 g/cm3
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More Answers
  • 2.a.  For a sphere, Volume = 4/3 π r3                           V = 4/3 x 3.14 x  (4.0 cm)3
  • = 4/3 x 3.14 x 64 cm3
  •   V =  268 cm3


  • 2.b.   D = m/V
  • FIRST: mass,  m = 5,900 g = 5.9 kg.
  • THEN:  Volume,  V = 2.2 m x 1.5 m x 0.60 m V = 1.98 m3
  • FINALLY: Density, D = m/V = 5.9 kg/1.98 m3 D = 3.0 kg/ m3