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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.
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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 isD=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.
