Density

Volume Volume is a measure of how much space an object takes up. A cube is a regular shaped object, so we can use a formula to determine its volume. Volume is a three dimensional measure, so the formula for volume of a cube has three parts. We can measure the volume of a cube using a ruler and some math.

Volume cont. The formula for the volume of a cube is: length * width *height. All the sides of a cube are equal in length, so knowing the length of one side is enough to find the volume. We always measure in metric units. Meters are the base metric unit for length, and usually in this class we will use centimeters when dealing with density. To measure the volume of a cube, we take a ruler and measure one side. Line the end of the cube up with the 0 cm mark, and read the length on the opposite edge of the cube.

Volume cont. When we find the volume of a cube, we multiply not only the numbers for length, width, and height, but the units too. Because of that, the unit for volume is simply cm * cm *cm , or cm3.

Mass Mass is a measure of how much matter is in an object. The mass of an object is measured using a balance. Grams are the base metric unit for mass, and we will use them in this class when we calculate density.

Density Density is a calculation of how tightly packed the molecules in a substance are. Density is calculated by determining the amount of mass per unit of volume. Density is a property of matter, just like color, melting point, freezing point, or conductivity. This means that the density of 100kgs of gold and 1 mg of gold will be exactly the same.

Density A very dense object has tightly packed molecules. Think of an example of something that is dense. A less dense object has more space between molecules. Think of an example of something that is less dense than your first example or has a low density.

Density cont. Density cannot be measured, only calculated. We measure the mass and volume of a cube, and we then use those measurements to calculate density. The formula for density is D=mass/volume, which is read as density is equal to the mass of an object per unit of volume of the object. Density is a measure of units of mass per unit of volume, so common units for density are grams per cubic centimeter, or g/cm3, or g/mL.