Q. Why does a hydrometer float higher in pure milk than diluted milk?
Answer: Buoyant force depends on density of liquid
Notes: Pure milk's higher density increases buoyant force, making hydrometer float higher. Archimedes’ principle relates liquid density to floating objects' positions. In diluted milk, lower density provides less buoyant force, causing hydrometer to sink deeper. Hydrometers measure specific gravity using this physical property.