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प्रश्न
Define the 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 the solid at the point of contact measured inside the liquid is called the angle of contact.
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संबंधित प्रश्न
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(d) feel a net force in one direction.
Consider a small surface area of 1 mm2 at the top of a mercury drop of radius 4.0 mm. Find the force exerted on this area (a) by the air above it (b) by the mercury below it and (c) by the mercury surface in contact with it. Atmospheric pressure = 1.0 × 105 Pa and surface tension of mercury = 0.465 N m−1. Neglect the effect of gravity. Assume all numbers to be exact.
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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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A metal piece of mass 160 g lies in equilibrium inside a glass of water. The piece touches the bottom of the glass at a small number of points. If the density of the metal is 8000 kg/m3, find the normal force exerted by the bottom of the glass on the metal piece.
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Define angle of contact.
