Measurement as a Generalization - Unpacked with its Concepts
Objects have properties or attributes that can be measured with different accuracies depending on the selection and use of a measurement system, units, tools, and purpose of the measurement.
Measuring is a process that starts with the identification of something to measure - a property of an object or event, then a selection of a measuring system and appropriate unit (standard or non standard), and finally a process to iterate the unit across the unknown object or event to be measured.
Primary
- Properties can be counted.
- Conservation of number - the number of objects does not change with the position of the objects.
- Conservation of length - length of an object does not change when its position is changed or its shape is altered by bending.
- Objects can be used to compare other objects.
- Measurement is a way of detecting change.
- Linear measurement is the distance between two points.
- Volume is the measurement of space an object occupies.
- Area measures the surface of an object.
- A standard unit of measurement helps communication.
- When the thermometer goes up the temperature is hotter.
- Measurement helps in making better observations.
- Scales measure mass and weight.
- Measuring cups measure volume
- Measurements can be compared.
- Measurement is used in everyday life (recipes, plans, designing, building)
- Time is the measurement of years divided into seconds, minutes, hours, days, weeks, months, decades, centuries.
- Mathematics can be used to solve problems with time.
- Time is communicated in standard units.
- The duration of an event from the beginning to the end is measured in time.
- Time represents past, present, and future events.
Intermediate
- Conservation of volume - volume of an object or substance does not change when the position and shape of the object or substance change position.
- Conservation of mass - mass of an object or substance does not change when the postion or shape of the object or substance changes.
- Conservation of area - area of a surface does not change when the position of the surface changes position.
- Properties and change of properties can be quantified.
- All measurement is relative to a unit, usually a standard unit.
- Scale is proportional.
- Measurement helps in making more accurate observations.
- Quantitative estimates of familiar lengths, weights, and time intervals can be confirmed by measurement.
- Measurement helps in making better observations.
- Rulers are used to measure linear measurement.
- Scales measure mass and weight.
- Measuring cups measure volume.
- Measurements can be compared.
- Measurement is used in everyday life (recipes, plans, designing, building).
- Rate is based on time.
- Standard units include:
- Linear measurement standard units are cm, m, km, inch, foot, yard, mile
- Volume- standard units include liter, ml, cup, pint, quart, gallon
- Time - measure in units of seconds, minutes, hours, days, weeks, months, years, decades, centuries. Time is used to order events. Twenty-four hours in a day, about 30 days in a month, 365 days in a year, 52 weeks in a year, 12 months in a year. Calendar is used to measure time. Clocks are used to measure time. Clocks can be analog and digital. A day is divided into daytime and nighttime. Time is determined by Earth's movement. Time is cyclic (seasons, days of weeks, months).
- Temperature measures hot and cold. Degrees in Celsius and Fahrenheit are standard units of temperature
- Mass - standard units are g, kg, pounds, ounces, tons
Middle
- All measurement has error.
- Scale is a proportional relationship of characteristics, properties, or relationships within a system as its dimensions are increased or decreased.
- Rate involves a measure of change for a part relative to a whole (birth rate as part of population growth and comparing one measured quantity to another measured quantity (km per hour).
Dr. Robert Sweetland's Notes ©