HELP: Science Measurement Review & Additional Resources


  • Measurements (quantitative observations) are more useful than qualitative observations.
  • You should make measurements, even estimated ones, whenever possible.
  • The system of units for measurements in physics is the SI system.
  • At this time, the fundamental quantities are length, mass, and time.
  • The SI unit for length is the meter and the standard meter is the distance light travels in \frac{1}{299792458} second in a vacuum.
  • The SI unit for time is the second and the standard second is based on of the frequency of one type of radiation emitted by a cesium-133 atom.
  • The SI unit for mass is the kilogram and is based on a mass stored in France.
  • Prefixes are used to change SI units by powers of ten. 

Additional Resources

Jump to 0:53 in the timeline to find the information on measurement and units in this video.

US Customary units vs Metric Units

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Last modified: Wednesday, 27 April 2016, 11:52 AM