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Is Matter Around Us Pure — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceIs Matter Around Us Pure3 Marks
Question
How is cream separated form milk?
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Answer

Centrifugation is used to separate cream from milk. Milk is a suspension of tiny droplets of oil in a watery liquid. It is put in closed container in a big centrifuge machine. When machine is switched on, milk is rotated at very high speed in its container. The cream being lighter floats over the skimmed milk and then can be removed.

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