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Define angle of contact.

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प्रश्न

Define angle of contact.

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उत्तर

When a liquid is in contact with a solid, the angle between the tangent drawn to the free surface of the liquid and the surface of solid at the point of contact measured inside the liquid is called the angle of contact.

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अध्याय 2: Mechanical Properties of fluids - Short Answer I

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एससीईआरटी महाराष्ट्र Physics [English] Standard 12 Maharashtra State Board
अध्याय 2 Mechanical Properties of fluids
Short Answer I | Q 3 (ii)

वीडियो ट्यूटोरियलVIEW ALL [1]

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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(α for water = 2.7×10-3/°C)


Derive an expression for excess pressure inside a drop of liquid.


Angle of contact for the pair of pure water with clean glass is _______.


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Water rises to a height 3.2 cm in a glass capillary tube. Find the height to which the same water will rise in another glass capillary having half area of cross section.


Explain why A drop of liquid under no external forces is always spherical in shape


What is the excess pressure inside a bubble of soap solution of radius 5.00 mm, given that the surface tension of soap solution at the temperature (20 °C) is 2.50 × 10–2 N m–1? If an air bubble of the same dimension were formed at depth of 40.0 cm inside a container containing the soap solution (of relative density 1.20), what would be the pressure inside the bubble? (1 atmospheric pressure is 1.01 × 105 Pa).


Two narrow bores of diameters 3.0 mm and 6.0 mm are joined together to form a U-tube open at both ends. If the U-tube contains water, what is the difference in its levels in the two limbs of the tube? Surface tension of water at the temperature of the experiment is 7.3 × 10–2 N m–1. Take the angle of contact to be zero and density of water to be 1.0 × 103 kg m–3 (g = 9.8 m s–2)


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Show that the surface tension of a liquid is numerically equal to the surface energy per unit
area.


State any two characteristics of the angle of contact


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By a surface of a liquid we mean


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(a) the material of the solid
(b) the material of the liquid
(c) the shape of the solid
(d) the mass of the solid


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A barometer is constructed with its tube having radius 1.0 mm. Assume that the surface of mercury in the tube is spherical in shape. If the atmospheric pressure is equal to 76 cm of mercury, what will be the height raised in the barometer tube? The contact angle of mercury with glass = 135° and surface tension of mercury = 0.465 N m−1. Density of mercury = 13600 kg m−3. 


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If the surface tension of a soap solution is 3 × 10-2 N/m then the work done in forming a soap film of 20 cm × 5 cm will be ______.


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)


A molecule of water on the surface experiences a net ______.


The upward force of 105 dyne due to surface tension is balanced by the force due to the weight of the water column and 'h' is the height of water in the capillary. The inner circumference of the capillary is ______.

(surface tension of water = 7 × 10-2 N/m)


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[Take surface tension of water T = 7.3 × 10-2 Nm-1, angle of contact = 0, g = 10 ms-2 and density of water = 1.0 × 103 kgm-3]


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