# Surface Tension

Surface tension, abbreviated as \( \sigma \) (Greek symbol sigma), is the energy or force at the surface of a liquid that holds it together.

## Surface tension formula |
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\(\large{ \sigma = \frac{F}{l} }\) \(\large{ \sigma = \frac{ \rho \; v^2 \; l_c }{ We } }\) |
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Symbol |
English |
Metric |

\(\large{ \sigma }\) (Greek symbol sigma) = surface tension | \(\large{\frac{lbf}{ft}}\) | \(\large{\frac{N}{m}}\) |

\(\large{ l_c }\) = characteristic length | \(\large{ ft }\) | \(\large{ m }\) |

\(\large{ \rho }\) (Greek symbol rho) = density of mass | \(\large{\frac{lbm}{ft^3}}\) | \(\large{\frac{kg}{m^3}}\) |

\(\large{ F }\) = force per unit length | \(\large{ lbf }\) | \(\large{N}\) |

\(\large{ l }\) = length in which force acts | \(\large{ ft }\) | \(\large{ m }\) |

\(\large{ v }\) = velocity of fluid | \(\large{\frac{ft}{sec}}\) | \(\large{\frac{m}{s}}\) |

\(\large{ We }\) = Weber number | \(\large{ dimensionless }\) |

Tags: Strain and Stress Equations Force Equations Soil Equations