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प्रश्न
Define angle of contact.
उत्तर १
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.
उत्तर २
The angle of contact (θ) between a liquid and a solid surface is defined as the angle between the tangents drawn to the free surface of the liquid and the surface of the solid at the point of contact, measured within the liquid.
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