Measurement

1
Measurement

• What is the question that most kids ask while on
  a long trip?

2
Most objects have multiple attributes that are
measurable.

• Find area to determine how much carpet to cover
  the floor of a room.
• Measure shoulder width, length from waist to neck
  to determine what size of sweater to knit.
• Measure weight to determine if an airline needs
  to charge more for a suitcase that will be
  transported on an airplane.

3
There is a process that we use to measure.

• Identify attribute
• Select unit
• Determine amount.

4
Units

• The units that we use are arbitrary as opposed to
  absolute.
• All units were invented by people.

5
Time

• 3000 years ago, Babylonians divided day into 12
  daytime hours and 12 nighttime hours.
• Greeks made the 24 hour day with all hours of
  equal length.
• In 1330 the hour was standardized.
• When were time zones established? Why? How do
  they work?

6
Length

• Cubit Point of elbow to outstretched middle
  finger.
• Foot Length of Hercules foot, Length of King
  Charlemagnes foot
• Yard Length from tip King Edgar Is nose to
  middle finger of his outstretched arm
• Weight Barleycorn, Seed of carrot plant (carat)

7
Avoirdupois system

• Troy system Used for precious metals and gems -
  12 ounces per pound
• Apothecaries system Used for small amounts -
  16 ounces per pound

8
Volume/capacity

• Dry volume oz., cup, pt., qt., gal., peck,
  bushel
• Liquid volume tsp., tbsp., oz., c., pt., qt.,
  gal. Page 657

9
Temperature

• Fahrenheit
• Celsius
• Kelvin

10
Other Measurements

• Sound Decibels
• Speed Miles per hour
• Fuel Consumption Miles per gallon
• Light intensity Candela
• Electric current Amperes
• Efficiency Production/Time
• Infant mortality Deaths/1000 live births

11
Measurement is a function.

• Amount Number that
• to be corresponds
• measured to amount

12
Virtually all measurements are approximations.
13
Precision and accuracy are not the same thing.

• Accuracy is skill in measuring.
• The level of precision is determined by the unit
  of measurement that is used. For example
  measuring your height in feet is more precise
  than measuring your height in yards.

14
Different attributes of an object are generally
not related in simple ways.