Density

Definition

Density is a measure of mass per unit volume. It is typically expressed in units such as grams per cubic centimeter (g/cm³) or kilograms per cubic meter (kg/m³).

5 Must Know Facts For Your Next Test

1. Density is calculated using the formula $\rho = \frac{m}{V}$, where $\rho$ is density, $m$ is mass, and $V$ is volume.
2. The density of a substance can help identify it, as different materials have characteristic densities.
3. Temperature and pressure can affect the density of a substance; typically, increasing temperature decreases density while increasing pressure increases density.
4. Water has a maximum density at 4°C, which is approximately 1 g/cm³.
5. Density plays a crucial role in buoyancy; an object will float in a fluid if its density is less than that of the fluid.

Review Questions

• What formula is used to calculate the density of an object?
• How does temperature generally affect the density of most substances?
• Why does an object with lower density than water float when placed in water?

Related terms

Mass:

The quantity of matter in an object, usually measured in grams or kilograms.

Volume:

The amount of space occupied by an object or substance, typically measured in liters or cubic meters.

Buoyancy: The ability or tendency of an object to float in a fluid due to differences in density.