B. Gravitational force C. Surface tension D. Viscosity Ans: C Surface tension is the property of the surface of a liquid that allows it to resist an external force due to the cohesive nature of its molecules. In a ball pen, surface tension helps to keep the ink in place within the reservoir and ensures a controlled flow of ink onto the ball and then to the writing surface.
Soap solution used for cleaning purpose appears cloudy. This is due to the fact that soap micelles can
Asked in UPSC CDS 2 2019 · Horticulture Development Officer(HDO) 2018 · Topic: Optics (Diffraction: Fraunhofer and Fresnel diffraction, diffraction grating)
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