question_answer

A capillary tube of radius r is dipped in a liquid of density r and surface tension S. If the angle of contact is q, the pressure difference between the two surfaces in the beaker and the capillary

A)             \[\frac{S}{r}\cos \theta \]

B)                      \[\frac{2S}{r}\cos \theta \]

C)             \[\frac{S}{r\cos \theta }\]       

D)             \[\frac{2S}{r\cos \theta }\]