fluid mechanics A drop of water at 20 degree C is forming un

fluid mechanics

A drop of water at 20 degree C is forming under a solid surface. The configuration just before separating and falling as a drop is shown in the figure. Assume the forming drop has the volume of a hemisphere. What is the diameter (D) of the hemisphere just before separating?

Solution

Weight of the drop   = Force of surface tension

Density * Volume * g   = 0.073 * perimeter

density * 2 * pi * D^3 / 24 * 9.8 = 0.073 * pi * D

D^2   = 0.073 * 24 / ( 19.6 * 1000)

D = 9.4545 mm