A small quantity of n-octane is placed in a wide test tube at 20degrees C and two capillaries are inserted vertically and immersedto the same depth. The radii of the capillaries are unknown but areof the order of 0.1 and 0.01 mm. Air is blown through eachcapillary in turn and the pressure necessary to just produce a slowstream of bubbles is recorded on a manometer filled with water.Show that the surface tension of each test liquid may be expressedas K(h1 – h2) where h1 and h2 are the two manometer readings and Kis a constant for the apparatus.
