You probably have an intuitive feeling for density in the materials you use often. For example, sponges are low in density; they have a low mass per unit volume. You are not surprised when a large sponge is easy to lift.
In contrast, iron is dense. If you pick up an iron skillet, you expect it to be heavy. Students, and even teachers, often confuse mass and density. The words heavy and light on their own refer to mass, and not density. A very large sponge may weigh a lot have a high mass , but its density is low because it still weighs very little per unit of volume.
For density, you also need to consider the size, or volume, of the object. A concrete cube will weigh more than a cube of air the same size because it is denser Show credits Hide from Pitsco Lighter-Than-Air Flight Density is not something that is directly measured. Typically if you want to know the density of something you will weigh it and then measure its volume.
Another tricky thing about density is that you can't add densities. If I have a rock that is made up of two minerals, one with a density of 2. This is because both the mass and the volume of the two minerals will be added, and so when they are divided to get the density the result will be between the two.
Typical densities for gasses are on the order of thousandths of grams per cubic centimeter. Liquids often have densities of about 1. Solids are typically denser than liquids and gases as the particles are tightly packed with very little space among them. In liquids, particles are not very tightly packed, due to which, they are less dense than solids but denser than gases, which have free-flowing particles.
Types of Density. Usually, the density is of 2 types, one is absolute density, and the other is relative density. Relative density is also known as specific gravity, which is the ratio of the density of a material to the density of reference material.
Usually, the reference material is water. Specific gravity is a relative quantity with no units. Absolute density refers to the mass of any substance per unit volume of a material. For example, the density of gold is Units of Density. Applications of Density in Real Life.
Let's get an idea with an example from real life. Suppose you have two balloons. If two water samples have different volumes, they still share a common measurement: the density. Density is another measurement derived from SI basic units. The density of a material is defined as its mass per unit volume. In this example, each volume of water is different and therefore has a specific and unique mass. The mass of water is expressed in grams g or kilograms kg , and the volume is measured in liters L , cubic centimeters cm 3 , or milliliters mL.
If you have ever cooked in a kitchen, you have probably seen some sort of measuring cup, which allows the user to measure liquid volumes with reasonable accuracy. The measuring cup expresses liquid volume in the standard SI units of liters and milliliters. Most American measuring cups also measure liquid in the older system of cups and ounces. Scientists who work in a laboratory must be familiar with typical laboratory glassware, often called volumetric glassware. These may include beakers, a volumetric flask, an Erlenmeyer flask, and a graduated cylinder.
Each of these containers is used in a laboratory setting to measure liquid volumes for different purposes. Different substances have different densities, so density is often used as a method to identify a material. Comparing the densities of two materials can also predict how substances will interact. If the object has a lower density than water, it will float to the top of the water.
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