Question

Operation of hydrometer is based on which of the following?

• A. Archimedes principle
• B. Ohm's law
• C. Buoyant law
• D. newton's law

Answer 1

The correct option is A Archimedes principle

Hydrometer is a devide used to determine the specfifc density of liquids.

A hydrometer is usually made of glass, and consists of a cylindrical stem and a bulb weighted with mercury to make it float upright. The liquid to test is poured into a tall container and the hydrometer is gently lowered into the liquid until it floats freely. This is in accordance with the Archimedes' principle. The point at which the surface of the liquid touches the stem of the hydrometer correlates to specific gravity. Hydrometers usually contain a scale inside the stem, so that the person using it can read specific gravity.