Surely at some time, even if it was involuntary, you have found yourself in a shopping center full of people buying and you have thought that it was overwhelming. This same situation can be transferred to other scenarios such as public transport at rush hour, or a disco that receives a visit from an important DJ, that is, on a really special day. In these three scenarios, the density of people was very high. We understand by something dense, something that is very present in a given space. The more quantity there is in said space, the greater the density there will be. In the three specific examples, whether in the mall, public transport or the nightclub, there were a lot of people in a limited space. In that sense, the density that we found was very high. It is also applicable to the field of food, where for example, cocoa can be a good example. The greater the density of cocoa in the chocolate, the more bitter it will be. This can be good for those who like dark chocolate or bad for those who prefer a softer chocolate such as the one accompanied with milk.
What is density?
The word density has its origin in Latin, and is used in numerous fields of both social and natural sciences. It is the relationship that exists between the inhabitants of a municipality in its square kilometers expressed in inhabitant per square kilometer. Obviously, something is required to compare and draw a rational conclusion, since without it, everything we say will have enormous subjectivity. Why? In some regimes like communism they are used to living in communes and therefore high population density seems to be something that is given as normal. On the other hand, in other types of societies such as the capitalist one it is more normal to live alone on their private property. In addition, in these types of countries, the birth rate has also been reduced. Another phenomenon is also affecting the population density in Western countries. This is the abandonment of the countryside to migrate to the big cities and vice versa. On the one hand, young people who want to have everything at hand emigrate to live in important and large cities, increasing the density of the population, such as Barcelona or Madrid. On the other hand, others who seek more tranquility go to live in the neighboring towns where there are much fewer people and there is much more space. However, these people are in the minority. In fact, depending on which town it is, technological advances such as fiber optics are hard to come by.
If we go to the more scientific field, we find a similar reasoning. In this case, we talk about mass and volume. Density is nothing more than the amount of mass of a material that exists in a given volume, normally we talk about water. For example, young people experience it practically every weekend. The so-called bottle is the order of the day and, even if they do it unconsciously, they play with density. If they want a more alcoholic glass they will introduce a greater amount of alcohol, beer or the liquor they are consuming and a smaller amount of mixture, in this case, we are talking about Coca-Cola, Fanta or any fruit drink. On the other hand, if you want it softer, you should do the opposite step. Introduce a little alcohol into the glass and accompany it with a larger amount of soda. The International System states that it should be expressed in kilos per cubic meter. However, for practical reasons it is expressed in another way, basically because otherwise too small and difficult amounts would come out. To remedy this type of controversy, it was decided to coin the measure of gram per cubic centimeter. In this way, we have to read more normal numbers and, therefore, the interpretations and comparisons that scientists have to make are much easier than not with decimals and stranger numbers.
Let’s not forget that each matter has a certain density in its normal habitat. One of the best known is that of water, which 1 liter of water corresponds to a kilogram of mass, therefore, in this case we would say that its density is 1 kilo/liter. Obviously, in each case, we can go from one type of conversion to another, depending on the comfort of the numbers. Of course, at all times we must make sure that the equivalences that we are using are correct, since otherwise, we will be making mistakes when drawing conclusions. For practical purposes, density is also directly related to the fact that a body can float in water, or instead ends up sinking. As we have said before, density is directly related to mass and, therefore, those objects that have a larger density, such as a stone or a piece of wood, will sink, while a feather, for example, will float. no problem in the water. In people, it can also be applied to density when measuring the level of fat that we can have, calculating the amount of fat stored in our body in relation to our body weight. In this sense, it can be expressed as a percentage in which less than 20% is adequate for health, and less than 10% is correct for an aesthetic level. Muscle mass is also related to fat when trying to increase it and looking for the most appropriate diet and exercise routine to achieve our body goals. It seems incredible, but the density is also present in this area.
Density Benefits
However, knowing the density and everything that it entails can lead us to multiple benefits, although it may seem silly. The most outstanding advantages are the following:
- Do sociological studies. The density of the population allows sociological studies to be carried out. Know the areas where the square kilometer is more free and vice versa, and from here, try to find out the reasons that have led to this situation. This can even be related to the macroeconomic and microeconomic section to find out if the price of housing can be behind all this.
- Approve natural sciences. Density is something that is learned in Natural Sciences throughout Primary Education and Compulsory Secondary Education. Obviously, it is not essential to pass this topic, but it will help the final grade to be closer to passing, or if we have more ambitious goals, we can also be closer to achieving our objectives.
- Develop a professional career. In the field of physics or chemistry, there are highly reputable jobs. Therefore, even if it seems silly, density can be the beginning of finding what we like. If you are in class and you are passionate about it, do not stop, go ahead because you are facing the opportunity to get a good professional career looking for a job in Valencia.
- Shape our body. If we want to lower the fat density of our body, it will be necessary to perform a large number of cardiovascular exercises to burn that fat that we want to eradicate.
As you can see, density is present in numerous fields or areas of interest, and in many parts of our lives. For this reason, we must not underestimate and be clear about the definition of this term, its uses and, as we will see below, the ways that exist to obtain density.
How to Calculate Density?
We have talked about density, its properties, situations where we can find this term, but it is time to learn how to calculate it and obtain it from different precedents, such as if we make homemade syrup. In the case of the population it is very simple. We want to know how many inhabitants per square kilometer there are. Let’s see a very simple example but it will serve to illustrate it. On the one hand, we have 100 inhabitants and, on the other, let ‘s say they live in a town of 50 square kilometers. In this case, the inhabitants will have to be divided by the square kilometers, obtaining a total of 2 inhabitants per square kilometer. In the case of going to the natural sciences we have the same system. The mass expressed in grams must be divided by the volume expressed in cubic centimeters and from there we will obtain the density of the object in question. It is a simple relationship between two variables, but you have to be careful not to confuse the dividend of the divisor because then we would get really different indications.
When making comparisons between two objects we can find ourselves with the need to obtain what is known as relative density. To obtain this variable, the density of the two objects must be obtained initially, as we have stated above. Once we have the two densities, they should be divided, regardless of the order, although if we compare different relative densities, we establish a scale so that we can make a rational and meaningful comparison. The result is expressed without units, because in the end it is nothing more than a coefficient that we may need to make different types of comparisons. It has no use other than this type of comparison that we may need in case we are carrying out some type of scientific report that requires writing the final conclusions we have reached. However, what happens if we do not have the values of mass and volume at the time we want to calculate the density? Very easy. On the one hand, we must weigh the object on a scale to obtain its weight and, from there we will already have the mass, the first of the values necessary to carry out the density calculation. On the other hand, we need the volume. It’s enough sinking the object in the water, to make the difference of liquids and from there to obtain the volume. With the mass and the volume we have already explained previously how to calculate the density from the division.
Science has also advanced over the years, with the appearance of some instruments such as the hydrometer that allows the density to be calculated in a totally direct way without going through the procedure that we have explained previously, something that saves time and also the need to find someone have the ability to perform the calculation manually. Obviously, in this case, we just have to learn how to use a hydrometer. If we do not have the necessary budget to purchase this device, there is another very simple procedure that we can also apply. On the one hand, you have to weigh a completely empty glass, but it must be graduated to obtain the volume in a simple way. Subsequently, we weigh the glass filled with the matter from which we want to obtain the mass. The difference will be the mass, while the volume will be obtained on the adjustable scale of the glass. Definitely different ways to calculate density.