Nu (letter)

Nu (uppercase Ν, lowercase ν) is the 13th letter of the Greek alphabet. In the system of Greek numerals, it has a value of 50.

It is derived from the Phoenician letter Nun.

In modern Greek, the letter represents the voiced alveolar nasal consonant /n/.

In mathematics and science, the lowercase ν is commonly used to represent:

• Frequency in physics (especially electromagnetism).
• Kinematic viscosity in fluid mechanics.
• Poisson's ratio in materials science.
• A degree of freedom in statistics.
• The neutrino, an elementary particle in particle physics.

The uppercase Ν is rarely used as a symbol because it is visually identical to the Latin letter N.