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प्रश्न
In a beam of sunlight entering a room, we can sometimes see dust particles moving in a haphazard way in the air. Why do these dust particles move?
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उत्तर
When a beam of sunlight enters a room, suspended dust particles are seen moving haphazardly. This is because the dust particles are constantly hit by the fast moving particles of air and due to this remain suspended despite gravity acting on them. This is an example of Brownian motion.
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संबंधित प्रश्न
Give one difference between atoms and molecules.
What are the two conditions for the interconversion of states of matter ?
Write true or false for each statement. Rewrite the false statement correctly.
Matter cannot exist in different states.
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- Name the scientist who discovered this phenomenon.
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(c) What could liquid C be ?
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Define the term matter.
