When the prefix milli is used in the metric or SI system, a fundamental unit of measurement is multiplied by which factor?

The prefix milli in the metric or SI system signifies a factor of one-thousandth, or 10^-3. This means that when you see a unit preceded by milli, you are dealing with a measurement that is a fraction of the base unit. For example, one millimeter (mm) is one thousandth of a meter (m), which is expressed mathematically as 1 mm = 0.001 m or 1 mm = 10^-3 m.

Understanding this concept is crucial for converting units in the metric system and applying these conversions in practical situations, such as in electrical work where precise measurements can be essential for safety and efficiency.