“Atto. Zepto. Yotto.”
No, it’s not an alien language. Anson Wong, our resident 5-year-old genius, recently stopped by to explain the smallest units of measurement, and boy did we learn a lot!
What is the metric system?
Pretty much all of us have a basic understanding of the metric system (King Henry died by drinking chocolate milk!). The metric system is a standardized decimal system of measurement based on the meters, liters and grams, which measure length, volume and mass.
But did you know there are units of measurement even smaller than the milli prefix?
Smallest units of measurement
As Anson explained, sometimes scientists need to measure very, very small things in our universe, like the distance between protons in an atom.
Yocto is the smallest prefix on the metric system, equal to 10−24. It’s sometimes used to measure Planck length. Don’t know what Planck length is? Neither did we. Planck length is a unit of length that equals 1.616229(38)×10−35 meters. In theoretical physics, it is considered to be the shortest meaningful length. Anything shorter, the notion of space is meaningless. It’s so small that it’s not even equal to one yoctometer.
Anyway, that’s way above our heads.
From yocto, the measurements get bigger. One thousand yocto is equal to one zepto. A thousand zeptos gets you an atto. A grand of those makes a femto. Another 1,000 gives you a pico. A thousand pico makes a nano. One thousand nano makes a micro.
Then we enter familiar territory. One thousand micro make a milli. Ten milli jumps to centi, and 10 centi jumps to deci. Ten deci brings you back to base: either one meter, liter or gram, depending on the unit you’re using.
Phew! We feel like we’re back in high school physics.
Anson’s Answers features 5-year-old whiz kid Anson Wong. He has a college-level grasp on various areas of science, dreams of becoming the president and can speak multiple languages. Did you catch that he’s just 5 years old? Anson has a passion for teaching others and loves to share videos explaining the human body, the laws of physics and his ideas for the future. Grab a seat, because Professor Anson’s class is in session!