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प्रश्न
Define surface tension.
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उत्तर
Surface tension is defined as the force per unit length acting at right angles to an imaginary line drawn on the free surface of the liquid.
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संबंधित प्रश्न
The energy of the free surface of a liquid drop is 5π times the surface tension of the liquid. Find the diameter of the drop in C.G.S. system.
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Draw a neat labelled diagram showing forces acting on the meniscus of water in a capillary tube.
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The surface tension of water at 0ºc is 75·5 dyne/cm. Find surface tension of water at 25°C. [ α for water = 0·0021/°C ]
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Mercury has an angle of contact equal to 140° with soda lime glass. A narrow tube of radius 1.00 mm made of this glass is dipped in a trough containing mercury. By what amount does the mercury dip down in the tube relative to the liquid surface outside? Surface tension of mercury at the temperature of the experiment is 0.465 N m–1. Density of mercury = 13.6 × 103 kg m–3
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In a conical pendulum, a string of length 120 cm is fixed at rigid support and carries a mass
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Show that the surface tension of a liquid is numerically equal to the surface energy per unit
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A big drop of radius R is formed from 1000 droplets of water. The radius of a droplet will be _______
A) 10 R
B) R/10
C) R/100
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By a surface of a liquid we mean
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A 20 cm long capillary tube is dipped in water. The water rises up to 8 cm. If the entire arrangement is put in a freely falling elevator, the length of water column in the capillary tube will be
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(c) find different type of molecules in their range of influence
(d) feel a net force in one direction.
A 5.0 cm long straight piece of thread is kept on the surface of water. Find the force with which the surface on one side of the thread pulls it. Surface tension of water = 0.076 N m−1.
A capillary tube of radius 0.50 mm is dipped vertically in a pot of water. Find the difference between the pressure of the water in the tube 5.0 cm below the surface and the atmospheric pressure. Surface tension of water = 0.075 N m−1.
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A solid sphere of radius 5 cm floats in water. If a maximum load of 0.1 kg can be put on it without wetting the load, find the specific gravity of the material of the sphere.
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Derive an expression for capillary rise for a liquid having a concave meniscus.
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Twenty-seven droplets of water, each of radius 0.1 mm coalesce into a single drop. Find the change in surface energy. Surface tension of water is 0.072 N/m.
The surface tension of a liquid at critical temperature is ______
Two soap bubbles have a radius in the ratio of 2:3. Compare the works done in blowing these bubbles.
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The wettability of a surface by a liquid depends primarily on
Explain elasticity using intermolecular forces.
Mention the S.I unit and dimension of surface tension.
Obtain an expression for the excess of pressure inside a
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- liquid bubble
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A large number of liquid drops each of radius 'r' coalesce to form a big drop of radius 'R'. The energy released in the process in converted into kinetic energy of the big drop. The speed of the big drop is ______. (T = surface tension of liquid, p = density of liquid)
Under isothermal conditions, two soap bubbles of radii 'r1' and 'r2' coalesce to form a big drop. The radius of the big drop is ______.
Soap solution is used for cleaning dirty clothes because ______.
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Eight droplets of water each of radius 0.2 mm coalesce into a single drop. Find the decrease in the surface area.
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(Surface tension of water = 7 × 10-2 N/m)
Work done to blow a bubble of volume V is W. The work done in blowing a bubble of volume 2V will be ______.
A spherical liquid drop of radius R is divided into eight equal droplets. If surface tension is T, then the work done in this process will be ______.
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