
A soap bubble is being blown on a tube of radius The surface tension of the soap solution is and the bubble makes with the tube as shown in the figure. Find the excess of pressure over the atmosphere pressure in the tube (in )




Important Questions on Surface Tension and Viscosity

A soap film is made by dropping a circular frame of radius in soap solution. A bubble is formed by blowing air with speed in the form of a cylinder. Air stops after striking surface of soap bubble. Density of air is . The radius of the bubble is . The radius of the bubble when the soap bubble separates from the ring is Find the value of (where, surface tension of liquid is ).



A circular ring has inner and outer radii equal to and respectively. Mass of the ring is . It gently pulled out vertically from a water surface by a sensitive spring. When the spring is stretched from its equilibrium position the ring is on verge of being pulled out from the water surface. If spring constant is and , the surface tension of water(in ) is . Write the value of where is the greatest integer function.

A long thin walled capillary tube of mass and radius is partially immersed in a liquid of surface tension . The angle of contact for the liquid and the tube wall is . How much force(in ) is needed to hold the tube vertically? Neglect buoyancy force on the tube.
(Take , )


