"Deci-" comes from the Latin root for tenth. Its symbol is "d". Only a few things are measured by tenths; the most common is the decibel, used for sound intensity. Blood sugar levels are measured in milligrams of glucose per deciliter of blood (the normal range for humans being 70-110 mg/dL).
2. 10^-2 (Hundredth)
Answer: centi-
"Centi-" comes from the Latin root meaning hundred. Its symbol is "c". Its main use is for the centimeter unit of length; 2.54 centimeters = 1 inch. It is also sometimes used to measure rainfall, or map-to-scale ratios.
3. 10^-3 (Thousandth)
Answer: milli-
"Milli-" comes from the Latin root for one thousand. Its symbol is "m". This one has many uses, such as the millimeter for length. Small liquid amounts, especially liquid doses of medicine, are often measured in milliliters. Medicine tablet doses are mostly measured in milligrams.
4. 10^-6 (Millionth)
Answer: micro-
"Micro-" comes from the Greek root for small. It is the only prefix to have a non-English letter symbol, the lowercase Greek letter mu (μ), although sometimes "u" or "mc" is used. Bacteria are typically 1-10 micrometers in diameter; the smallest medicine doses are measured in micrograms (using the abbreviation mcg); the microsecond is typically used to measure very short periods of time.
5. 10^-9 (Billionth)
Answer: nano-
"Nano-" comes from the Greek word meaning dwarf. Its symbol is "n". One nanometer is the length a fingernail grows in one second; three gold atoms lined up would be about one nanometer long. The nanosecond is used in science for extremely short periods of time; for example, light travels in air 30 centimeters in about one nanosecond.
6. 10^-12 (Trillionth)
Answer: pico-
"Pico-" comes from the Spanish word "pico" meaning "peak, beak, bit". Its symbol is "p". The most common use for the trillionth unit of measure is the radius of atoms; the hydrogen atom has the smallest radius at 25 picometers, and the cesium atom has the largest at 260 picometers.
7. 10^-15 (Quadrillionth)
Answer: femto-
"Femto-" comes from the Danish word for fifteen. Its symbol is "f". This unit is often used to measure the mass of a virus (the HIV virus has a mass of about 1 femtogram). Also, a proton has a diameter of about 1.6 to 1.7 femtometers.
8. 10^-18 (Quintillionth)
Answer: atto-
"Atto-" is derived from the Danish word for eighteen. Its symbol is "a". Electrons and quarks fall in the attometer unit of length, and some probabilities are measured at or around the quintillionth interval.
9. 10^-21 (Sextillionth)
Answer: zepto-
"Zepto-" is a corruption of the Latin root "septem-" meaning seven (one sextillionth is 1000^-7). Its symbol is "z". The electric charge of an electron is about 160 zeptocoulombs; a zeptomole of substance contains 602 particles; a human insulin molecule has a mass of about 10 zeptograms.
10. 10^-24 (Septillionth)
Answer: yocto-
"Yocto-" comes from the Greek and Latin root "octo" meaning eight (one septillionth is 1000^-8). Its symbol is "y". Yoctograms are used to measure the mass of subatomic particles: protons and neutrons measure about 1.67 yg, and electrons are 0.0009 yg.
This quiz was reviewed by FunTrivia editor rossian before going online.
Any errors found in FunTrivia content are routinely corrected through our feedback system.