Density Concepts, Calculations, and Properties

Vocabulary flashcards covering the core concepts, formulas, units, and principles of density, mass, and volume from the lecture.

Density

The amount of mass per unit of volume, or a measurement of how tightly matter is packed together in a given space.

Archimedes

The Greek scientist who discovered the principle of density.

Water Displacement

A method used to determine the volume of an object by placing it into water in a graduated cylinder and measuring how much the water level rises.

Units of Density

Standard measurement units for density, expressed as $\text{g/cm}^3$ for solids or $\text{g/mL}$ for liquids.

Density Formula

The mathematical equation used to find density: $D = \frac{M}{V}$ ($\text{Density} = \frac{\text{Mass}}{\text{Volume}}$).

Mass Formula ($M$)

The equation derived from density used to find mass: $M = D \times V$.

Volume Formula ($V$)

The equation derived from density used to find volume: $V = \frac{M}{D}$, or for a rectangular prism, $\text{length} \times \text{width} \times \text{height}$.

Shape and Size Invariance

The rule stating that changing an object's shape or cutting it into pieces does not change its density; every substance has its own unique density.

Factors Affecting Density

Temperature and pressure, which are the only conditions that can affect the density of a substance.

Density of Water

The density standard of $1.0\,\text{g/mL}$ (or $1.0\,\text{g/cm}^3$), against which objects sink, float, or suspend.

Floating

The behavior of an object in a liquid when its density is lower than the liquid's density (such as having a density less than $1.0\,\text{g/cm}^3$ in water).

Sinking

The behavior of an object in a liquid when its density is higher than the liquid's density (such as having a density greater than $1.0\,\text{g/cm}^3$ in water).

Suspension

The state where an object neither sinks nor floats to the top because its density is equal to the density of the surrounding liquid.

Helium Balloon Buoyancy

The tendency of a helium balloon to rise because helium is less dense than the surrounding air.

Density Column

A container of multiple liquids stacked in layers that stay separated because each liquid possesses a different density.

Polystyrene Density

A value of $0.2\,\text{g/cm}^3$, which remains constant whether the polystyrene is in a whole block or cut into smaller slices.

Weight

A characteristic of an object that depends on gravity and changes when traveling from Earth to the Moon, unlike mass or volume.