What is density and how is it calculated?

What is density and how is it calculated?

• A. Density is volume per mass; density = volume / mass.
• B. Density is mass per area; mass per area.
• C. Density is energy per mass.
• D. Density is mass per volume; density = mass divided by volume.

Answer: (D)

Density tells you how much matter is packed into a given amount of space. It’s an intensive property, meaning it doesn’t depend on how much material you have. You find density by dividing the mass by the volume: density = mass / volume. Mass is how heavy the object is, and volume is how much space it occupies. For a regular-shaped object, volume is length × width × height; for an irregular object, you can measure volume by how much water it displaces when submerged. Common units are g/cm^3 for solids or kg/m^3 in SI. For example, if a block has a mass of 200 g and a volume of 100 cm^3, its density is 2 g/cm^3. Water at room temperature has a density of about 1 g/cm^3. Density helps explain buoyancy: objects with greater density than the surrounding liquid tend to sink, while less dense ones float. Descriptions like energy per mass or mass per area describe different quantities, so they aren’t density.

Density tells you how much matter is packed into a given amount of space. It’s an intensive property, meaning it doesn’t depend on how much material you have. You find density by dividing the mass by the volume: density = mass / volume. Mass is how heavy the object is, and volume is how much space it occupies. For a regular-shaped object, volume is length × width × height; for an irregular object, you can measure volume by how much water it displaces when submerged. Common units are g/cm^3 for solids or kg/m^3 in SI. For example, if a block has a mass of 200 g and a volume of 100 cm^3, its density is 2 g/cm^3. Water at room temperature has a density of about 1 g/cm^3. Density helps explain buoyancy: objects with greater density than the surrounding liquid tend to sink, while less dense ones float. Descriptions like energy per mass or mass per area describe different quantities, so they aren’t density.