What is the power of ten represented by the prefix 'femto'?

The prefix 'femto' is defined in the metric system and represents a factor of 10 to the power of negative fifteen, or 10^-15. This means that when you see a measurement using 'femto', it indicates that the value is a fraction of a unit that is one quadrillionth (1/1,000,000,000,000,000) of that unit.

The other prefixes listed represent different powers of ten:

• The prefix associated with 10^-18 is 'atto', which signifies one quintillionth.
• The prefix for 10^-12 is 'pico', which denotes one trillionth.
• The prefix for 10^-21 is 'zepto', representing one sextillionth.

Thus, femto's association with 10^-15 highlights its position in the metric system for measuring very small quantities, especially in fields such as physics and engineering where extremely small measurements are common.