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
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