Question

(a) name and state the principle used to check purity of milk by lactometer (b) write its two application

Answer 1

heya mate, nice question
here is your answer

name of the principal is Archimedes principle
statement : when a body is immersed fully or partially in a fluid, it experiences an upward force that is equal to the weight of the fluid displaced by it
principles: 1. it is used to design submarines and ships
2. hydrometer are used for determining density of liquids.

hope this helps u

Answer 2

Archimedes principle was used to check the purity of milk by lactometer..