Mu (letter) facts for kids

Mu (written as Μ for uppercase and μ for lowercase) is a special letter from the Greek alphabet. It's like the "M" in our alphabet!

People in Ancient Greece and today in Greece use Mu to make the "m" sound, just like in the word "monkey." In the old system of Greek numerals, Mu had a value of 40.

Many letters we use today came from Mu, like the letter M in the Roman alphabet (which English uses) and the letter М in the Cyrillic alphabet (used in languages like Russian).

What is Mu used for?

Mu isn't just a letter; it's also used in different areas of science and mathematics!

Mu in Math and Science

• In mathematics and statistics, the small letter μ is often used to show the "mean" of a group of numbers. The mean is just another word for the average. So, if you have a list of numbers, μ can represent their average value.
• It's also used for something called the Möbius function, which is a special rule in number theory.
• In physics, μ helps describe a few different things:
  • It can stand for the coefficient of friction. This tells you how much two surfaces rub against each other when they slide.
  • It's used for a very tiny unit of measurement called a micrometre. A micrometre is one-millionth of a meter – super small!
  • It also represents a tiny particle called a muon, which is a type of elementary particle, even smaller than an atom.

Images for kids

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  Greek letter mu

See also

In Spanish: Μ para niños