Question 3Electricity & Electronics - QMED

The correct answer is D) buoyancy of the indicator in the liquid being measured as compared to water. A hydrometer measures the specific gravity of a liquid by comparing the buoyancy of the hydrometer in the liquid to its buoyancy in pure water. The hydrometer sinks deeper in liquids that are less dense than water, and floats higher in liquids that are more dense than water. This difference in buoyancy is used to calculate the specific gravity, which is the ratio of the density of the liquid to the density of water. The other answer choices are incorrect because they do not accurately describe what a hydrometer measures. It does not compare the mass, density, or weight differences between the liquid and water, but rather the buoyancy difference.