Question

Cream from milk is separated by centrifugation because:

• A. the cream and milk have equal weight
• B. the cream is heavier than milk
• C. the cream sinks in the milk
• D. the cream is lighter than milk

Answer 1

The correct option is D the cream is lighter than milk

Cream is obtained from milk by the method of centrifugation. The principle of centrifugation is that when the mixture is spun rapidly the denser particles are pushed to the bottom and the lighter particles stay at the top.

While separating cream from milk, the milk is rotated at a very high speed. In this way, the denser particles settle at the bottom and the lighter ones float over the surface. Cream being lighter than milk, floats on the top.