The solid particles in a liquid are very small and pass through a filter paper.
For such particles the filtration technique cannot be used for separation. Such mixtures are separated by centrifugation. The principle is that the denser particles are forced to the bottom and the lighter particles stay at the top when spun rapidly.
• Take some full-cream milk in a test tube.
• Centrifuge it by using a centrifuging machine for two minutes. If a centrifuging machine is not available in the school, you can do this activity
at home by using a milk churner, used in the kitchen.
•we can use (i) how they separate cream from milk and (ii) how they make cheese (paneer) from milk.
• Used in diagnostic laboratories for blood and urine tests.
• Used in dairies and home to separate butter from cream.
• Used in washing machines to squeeze out water from wet clothes.