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The angle of contact at the interface of water-glass is 0°, Ethylalcohol-glass is 0°, Mercury-glass is 140° and Methyliodide- glass is 30°.

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प्रश्न

The angle of contact at the interface of water-glass is 0°, Ethylalcohol-glass is 0°, Mercury-glass is 140° and Methyliodide-glass is 30°. A glass capillary is put in a trough containing one of these four liquids. It is observed that the meniscus is convex. The liquid in the trough is ______.

पर्याय

  • water

  • ethylalcohol

  • mercury 

  • methyliodi

MCQ
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उत्तर

The angle of contact at the interface of water-glass is 0°, Ethylalcohol-glass is 0°, Mercury-glass is 140° and Methyliodide-glass is 30°. A glass capillary is put in a trough containing one of these four liquids. It is observed that the meniscus is convex. The liquid in the trough is mercury.

Explanation:

The meniscus of liquid is convex so the angle of contact will be the obtuse angle that happens in the case of mercury glass.

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पाठ 10: Mechanical Properties of Fluids - Exercises [पृष्ठ ७३]

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एनसीईआरटी एक्झांप्लर Physics Exemplar [English] Class 11
पाठ 10 Mechanical Properties of Fluids
Exercises | Q 10.5 | पृष्ठ ७३

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