Topic: The Metric System Do Now: Calculate the volume of Fe. What element is Fe? mass of Fe(s) = 15.9 g density of Fe(s) = 7.87 g/cm3

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Topic The Metric SystemDo Now Calculate the
volume of Fe. What element is Fe?mass of Fe(s)
15.9 g density of Fe(s) 7.87 g/cm3
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Measurement up to 1790Not a pretty picture!

• Measurement requires standard
• and until 1790s
• every region had own standard

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Standards

• standard something used as comparison
• for measuring
• standard must
• be available for everyone to use to check
  measurements
• be something in nature that is same everywhere
• never vary

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Systeme International (SI)

• based on metric system
• invented in 1790
• Larger smaller multiples of each unit related
  by powers of 10
• prefixes
• updated every few years (particularly in in 1960
  and 1991)

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Smaller Units

• 1/10 of a meter decimeter (dm)
• 1/100 of a meter centimeter (cm)
• 1/1000 of a meter millimeter (mm)
• Larger Units
• 10 meters dekameter (dam)
• 100 meters hectometer (hm)
• 1000 meters kilometer (km)

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Kids
Have
Dropped
Dead
Converting
Metric
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Ladder Method
KILO1000Units
HECTO100Units
DEKA10Units
DECI0.1Unit
CENTI0.01Unit
MILLI0.001Unit
4 km _________ m
How many jumps does it take?
4.
4000 m
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Prefixes in the SI System
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Fundamental or Base units

• The SI system has 7 fundamental units
• All other units of measurement can be derived
  from these base units
• You already know 4. What are they?

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7 Fundamental Quantities of SI
Abbreviation
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Derived Units

• Combinations of fundamental units
• Examples
• Speed (meters/second)
• Area (Length x Width)
• Volume (Length x Width x Height)
• Density (Mass / Volume)

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Prefixes

• prefixes can be used with all 7 fundamental
  units!
• Kilometer
• Milliliter
• Centigram
• Microsecond
• Nanokelvin

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1790 - Jefferson

• Proposed decimal-based measurement system for
  United States
• Didnt have prefix idea and system had too many
  names.and so we are stuck using feet, inches,
  cups, ounces, etc

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Prototype kilogram stored in vault in France
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So.Why is the SI more efficient then the US
system?