Measurement Units

Measurement Units, Symbols, and Prefixes

Like the rest of science and engineering, electronics relies heavily on the International System of Units, which is abbreviated SI.  The abbreviation SI comes from the French name Système International, and it’s basically the modern version of the metric system.  Electronics also have measurements and quantities with some very large and small values.  So, instead of a schematic with values like 1000 Ω or 1 x 103 Ω, you are likely to see 1 kΩ.  In this example, k is the metric prefix for one-thousand, and the Greek letter omega Ω is symbol for ohm, the SI unit of resistance.  


In this activity, you will:

  • Learn SI metric prefixes and units commonly used to describe electrical and electronic measurements
  • Convert from metric prefixes to values, use values in calculations, and then convert back:
    • With a paper, pencil and calculator method
    • With a script