Height of A Meniscus
The height h of a liquid column is given by:
where is the liquid-air surface tension (force/unit length), θ is the contact angle, ρ is the density of liquid (mass/volume), g is local gravitational field strength (force/unit mass), and r is radius of tube (length).
For a water-filled glass tube in air at standard laboratory conditions, γ = 0.0728 N/m at 20 °C, θ = 20° (0.35 rad), ρ is 1000 kg/m3, and g = 9.81 m/s2. For these values, the height of the water column is
Thus for a 4 m (13 ft) diameter glass tube in lab conditions given above (radius 2 m (6.6 ft)), the water would rise an unnoticeable 0.007 mm (0.00028 in). However, for a 4 cm (1.6 in) diameter tube (radius 2 cm (0.79 in)), the water would rise 0.7 mm (0.028 in), and for a 0.4 mm (0.016 in) diameter tube (radius 0.2 mm (0.0079 in)), the water would rise 70 mm (2.8 in).
Read more about this topic: Capillary Action
Famous quotes containing the words height of and/or height:
“There is a time of life somewhere between the sullen fugues of adolescence and the retrenchments of middle age when human nature becomes so absolutely absorbing one wants to be in the city constantly, even at the height of summer.”
—Edward Hoagland (b. 1932)
“The height of cleverness is being able to conceal it.”
—François, Duc De La Rochefoucauld (1613–1680)