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Good day.
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The topic is about force of attraction.
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Particles exert a certain force among themselves, and this force can be either cohesive or adhesive.
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Cohesive force is a force of attraction existing between particles which are of the same nature.
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That means they are particles of the same compound or substance, whereas adhesive force is also a type of force of attraction existing between particles.
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Of different substances.
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Now the extent at which cohesive and as adhesive force is present will determine several characteristics or appearances of a nature of a substance when it is contained in another substance.
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So for example we have a test tube that is greasy that means its outer or its side walls contain oil and and that the side glass are wrapped with oil.
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It is found out that for such type of test tube, the miniscus of the water, that means the surface of the water appears flat.
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So this is the case when the test tube is greasy.
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So here we note, we see that the miniscus is flat.
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Whereas when the test tube is clean, it's seen...