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A mercury drop of radius 1 cm is sprayed into 106 droplets of equal size. Calculate the energy expended if surface tension of mercury* is .


The lower end of a capillary tube of diameter 2.00 mm is dipped 8.00 cm below the surface of water in a beaker. What is the pressure required in the tube to blow a bubble at its end in water? Also calculate the excess pressure. [Surface tension of water  density of water = 103kg/m3, 1 atmosphere 


The limbs of a manometer consist of uniform capillary tubes of radii . Find out the correct pressure difference if the level of the liquid (density 103 kg/m3, surface tension ) in narrower tube stands 0.2 m above that in the broader tube. 


Two separate air bubbles (radii 0.002 m and 0.004 m) formed of the same liquid (surface tension 0.07 N/m) come together to form a double bubble. Find the radius and the sense of curvature of the internal film surface common to both the bubbles. 


A glass capillary sealed at the upper end is of length 0.11 m and internal diameter . The tube is immersed vertically into a liquid of surface tension . To what length has the capillary to be immersed so that the liquid level inside and outside the capillary becomes the same? What will happen to the water level inside the capillary if the seal is now broken?


A conical glass tube of length 0.1 m has diameters 10–3 and  at the ends. When it is just immersed in a liquid at 0oC with larger diameter in contact with it, the liquid rises to  in the tube. If another cylindrical glass capillary tube B is immersed in the same liquid at 0oC, the liquid rises to  height. The rise of liquid in the tube B is only  when the liquid is at 50oC. Find the rate at which the surface tension changes with temperature considering the change to be linear. The density of the liquid is  and angle of contact is zero. Effect of temperature on density of liquid and glass is negligible.



A rectangular container with base  contains 5 kg of water. What is the pressure exerted by water at the bottom of the container? 


A cylindrical jar of cross-sectional area 0.01 m2 is filled with water to a height of 50 cm. It carries a tight-fitting piston of negligible mass. What is the pressure at the bottom of the jar when a mass 1 kg is placed on the piston? Take g = 10 ms–2.


A hydraulic lift is used to lift a car of mass 3000 kg. The cross-sectional area of the lift on which the car is supported is . What is the pressure on the smaller piston, if both the pistons are at the same horizontal level?

Take g =10 ms–2


A ring is cut from a platinum tube of 8.5 cm internal and 8.7 cm external diameter. It is supported horizontally from a pan of a balance so that it comes in contact with the water in a glass vessel. What is the surface tension of water is an extra 3.97 g weight is required to pull it away from water? (g = 980 cm/s2)