Solution 1.63
The surface tension forces YdL1 and YdL2 have a slight vertical component. Thus summation of
forces in the vertical gives the result
z 2 1
12
F 0 2YdL sin(d /2)
2YdL sin(d /2) pdA
==
+ −
But dA = dL1dL2 and sin(d
/2) d
/2, so we may solve for the pressure difference: