Question

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

Answer 1

Archimedes' principle
b) Two applications are :
    1) Floatation of ships and submarines
    2) Design of Hydrometers to find the densities of liquids.

Answer 2

a) The principle is Archimedes Principle.
It states that " When an object is fully or partially submerged in any liquid then the buoyant force acting on the object is equal to weight of liquid displaced by the object"

b) Two applications are --->

1) Designing ships and submarines.
2) Hydrometers that calculate the relative density of liquids.

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