Bennett Mechanical Comprehension Practice Test

Density is essential for understanding buoyancy in liquids because it defines how much mass of a substance is contained within a specific volume. When an object is placed in a liquid, it displaces a volume of that liquid. The relationship between the density of the object and the density of the liquid determines whether the object will float or sink.

If the density of the object is less than the density of the liquid, the object will float due to the buoyant force acting upon it, which is equal to the weight of the displaced liquid. Conversely, if the density of the object is greater than that of the liquid, it will sink.

This principle is crucial in applications ranging from naval architecture to everyday scenarios, such as determining why some objects float in water while others do not. The other properties listed—viscosity, temperature, and mass—may influence certain behaviors of liquids or solids, but they do not directly determine the buoyant behavior of objects in a fluid.