Dyne

For other uses, see Dyne (disambiguation).

In physics, the dyne (symbol "dyn", from Greek δύναμις (dynamis) meaning power, force) is a unit of force specified in the centimetre-gram-second (CGS) system of units, a predecessor of the modern SI. One dyne is equal to 10 µN (micronewtons), or to 10 nsn (nanosthenes) in the old metre-tonne-second system of units. Equivalently, the dyne is defined as "the force required to accelerate a mass of one gram at a rate of one centimetre per second squared":

1 dyn = 1 g·cm/s² = 10⁻⁵ kg·m/s² = 10⁻⁵ N

1 Newton = 1 kg•m/s² = 10⁵ g•cm/s² = 10 ⁵ dyne

The dyne per centimetre is the unit traditionally used to measure surface tension. For example, the surface tension of distilled water is 72 dyn/cm at 25 °C (77 °F);^[1] in SI units this is 72×10⁻³ N/m or 72 mN/m.