Question:

Example 2.7: A capillary tube of radius 5 * 10 ^ – 4 m is immersed in a beaker filled with mercury. The mercury level inside the tube is found to be 8 * 10 ^ – 3 below the level of reservoir. Determine the angle of contact between mercury and glass. Surface tension of mercury is 0.465 N/m and its density is 13.6 * 10 ^ 3 * kg / (m ^ 3) . (g = 9.8m / (s ^ 2)