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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

The surface tension of a liquid at critical temperature is ______ - Physics

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प्रश्न

The surface tension of a liquid at critical temperature is ______ 

पर्याय

  • Infinity

  • Zero

  • Same as any other temperature

  • Can not be determined

MCQ
रिकाम्या जागा भरा

उत्तर

The surface tension of a liquid at critical temperature is  Zero.

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पाठ 2: Mechanical Properties of fluids - MCQ’s

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संबंधित प्रश्‍न

Derive Laplace’s law for spherical membrane of bubble due to surface tension.


A raindrop of diameter 4 mm is about to fall on the ground. Calculate the pressure inside the raindrop. [Surface tension of water T = 0.072 N/m, atmospheric pressure = 1.013 x 105 N/m2 ]


Define the angle of contact.


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.


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Explain why The angle of contact of mercury with glass is obtuse, while that of water with glass is acute


Explain why Surface tension of a liquid is independent of the area of the surface


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


Fill in the blanks using the word(s) from the list appended with each statement

Surface tension of liquids generally . . . with temperatures (increases / decreases)


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


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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The contact angle between pure water and pure silver is 90°. If a capillary tube made of silver is dipped at one end in pure water, will the water rise in the capillary?


A uniform vertical tube of circular cross section contains a liquid. The contact angle is 90°. Consider a diameter of the tube lying in the surface of the liquid. The surface to the right of this diameter pulls the surface on the left of it. What keeps the surface on the left in equilibrium?


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(a) the material
(b) the length
(c) the outer radius
(d) the inner radius of the tube


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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) The surface tension of the liquid must be zero.
(b) The contact angle must be 90°.
(c) The surface tension may be zero.
(d) The contact angle may be 90°.


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A drop of mercury of radius 2 mm is split into 8 identical droplets. Find the increase in surface energy. Surface tension of mercury = 0.465 J m−2.


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(T = surface tension of soap solution).


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