Question

Lactometer is based on

• A. Bernoulli's theorem
• B. Archimedes principle
• C. First law of thermodynamics
• D. None

Answer 1

The correct option is B

Archimedes principle

The explanation for the correct option:

Option B: Archimedes principle:

1. Lactometer is used to measure the purity of milk.
2. 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.
3. Lactometer compares the density of the given milk with the density of water, which gives the relative density of the milk.

The explanation for the incorrect option:

Option A: Bernoulli's theorem:

Bernoulli's theorem states that as the speed of moving fluid increases, the pressure within the fluid decreases.

Option C: First law of thermodynamics:

The first law of thermodynamics states that energy can neither be created nor be lost, it can only be transformed from one form to another.

Hence, the correct answer is Option B.