Question

Lactometer based on the

(1) Newton's first law

(2) Law of conservation of momentum

(3) Principle of Archimedes

(4) Newton's second law

Answer 1

Correct option is (3) Principle of Archimedes

• Lactometer is used to measure the purity of milk.
• Lactometer works on Archimedes' principle which states that when a body is partially or completely immersed in a liquid, it experiences an upthrust that is equal to the weight of the body.
• Lactometer compares the density of the given milk with the density of water, which gives the relative density of the milk.