I do not know anyone who has at least once in his life been fascinated by the splendour of the Sun. Since the first civilizations and cultures, the Sun has been very present and relevant in them. The Sun, being the closest star to Earth, allows us to study its operation and structure. Like all stars, it is in constant activity and evolution, and these, when they arrive in Earth, go a little unnoticed, but it does not take away the fact that they are very important. For this reason, my work tutor Anicet Cosialls, and I, a student, Belén Vicente, have carried out an astrophysical study where we have study some phenomena that take place in the Sun, as well as some of its magnitudes. The entire study has been carried out with the simplest possible material available to everyone and using methods as simple as the darkroom. In this work we have studied and estimate the rotation period, the solar constant, the luminosity, the distance from the Earth to the Sun, the temperature, the gravitation field, the mass, the life cycle and the CME’s speed. In addition, we observed the Sun with different methodologies.

This research presents the study of the non-linear and unstationary aerodynamics associated with the autorotation movement exhibited by the samaras with a paper model (that we will refer to as Twister or paper helicopter).

The investigation is divided in three sections. The first one consists in a bibliographic study of the physical principles related to aerodynamics and the rotation dynamics.

Then, in the second part, of experimental aspect, we have designed and built different paper helicopters to find which characteristics observed in the samaras (we have elaborated an herbal to know which geometric features are the most differentiated between the various species) allow a maximum descent time. This research, has been developed through the cinematic analysis of the frames captured by a camera of video, thanks to the analysing programme Tracker.

Finally, we have intended to give an explanation at the helicopter movements using the physic laws studied in the first section.

In this research work we have tried to bring together all that is necessary to understand how sundials work.

It consists of three parts: first the theoretical part, in which we carried out some research on the history of sundials, the movements of the Sun in the different seasons, and the different types of sundials. Afterwards, in the practical part we have studied how the gnomon shadow changes during the day and during the year. We have also designed and built a vertical sundial for our secondary school.

In this essay we are going to get ready to discover the secrets the Kelvin generator hides, a device that creates high electrostatic potential differences from the fall of water streams through two metallic rings. The project is very interesting since, in spite of being a spectacular device, the Kelvin generator is quite unknown in our territory and there is not much published information; because of that one of the objectives of this study is to introduce it to the society around us. This work is distributed, in general, in four parts: the previous knowledge, where all the concepts related with the generator’s properties are clarified; the design and construction of the device, where we make our own model; the realization of the necessary tests in different conditions of structure and of environment; the obtained results, analysis and discussion, where we comment the extracted information from the different tests. The conclusions we have extracted about the generator’s operation from the tables of results are that the device only works with polar liquids and that the potential difference is influenced by the structural and environmental conditions as the humidity, the type of used liquid, the diameter and the length of the skirt of the rings and the speed water streams pierce the rings.

The Moon is the only natural satellite of the Earth and the only body in the solar system we can see without the help of any instrument. For this reason with this research essay has been tried, to show the moon from a closer view. By capturing different images of each part of the Moon and by mean of careful study of each of them, a map composition that shows our satellite has been built. Then the same map in 3D was set up. Also were identified the more relevant lunar craters and formations and the characteristics, height and diameter of some of them were studied. We can conclude that with the proper tools it is possible to deepen into the study of lunar morphology.

Key words: lunar map, lunar crater, lunar topography, morphometric data

This research essay was an initiative of Anicet Cosialls. When I read the title, it caught my attention since it combined two things I like, Physics and Music, therefore, I found a good way to learn more about these two concepts.

The flute is an instrument consisting of a tube mechanism which by air runs.

By means of this project we will explain how some tubes can sound using basic sound concepts, such as sound it self, frequency of sound, and the existence of waves that make it possible. How to build tubes with different sounds and colors will be shown and finally, 40 tubes will be built and a musical performance will be played using all this tubes.

Es dissenya i construeix  un telescopi reflector (newtonià) amb materials casolans, i se'n determinen  les seves característiques tècniques: nombre d’augments, resolució, lluminositat etc.

In this research essay it is reviewed the actual knowledge about the fundamental particles which form the matter, and also their interactions. This model is known as the Standard Model.

Moreover, a cloud chamber has been designed and built. With this cloud chamber there have been carried out different experiments  in order to detect the cosmic radiation and the presence of some subatomic particles

From the beginnings of life, man has considered to study the world but the universe that wraps him. The Egyptians and the Greeks were the first ones that started doing estimations and calculations of the simplest astronomic measures.

My essay consists in doing some easy astronomic estimations, from experiments previously done: as one example, the dark box, created by myself, or the experiment of the calculation of the distance between the Earth and the Moon, which was done for the first time my physics teacher, Anicet Cosialls.

To be able to do these experiments, it is necessary to have neither technological or very complicated devices, nor impressive telescopes; the whole material that I have used, is the one that can be found in any laboratory or that you  can make yourself.