Contextualization
The magnetic field is a fundamental component of the universe around us. From the early experiments of Oersted and Ampère to modern applications in cutting-edge technology, the study of the magnetic field has been crucial for scientific and technological development.
The magnetic field generated by a coil, also known as a helical magnetic field, is one of the most intriguing concepts in the study of electromagnetism. The coil, which is simply a conductor wire wound in a spiral, when crossed by an electric current, generates a magnetic field along its axis. This phenomenon has vast practical applications, ranging from the small electric motors in our household appliances to the magnetic resonance technology used in hospitals.
We live in a world increasingly dependent on the use of magnetic fields. In our daily lives, we find applications of coils in speakers, electric motors, transformers, and even in our power grid. In the field of medicine, the use of coils is vital in magnetic resonance technology, which allows doctors to visualize the inside of our bodies without the need for surgery.
To delve deeper into the concepts of magnetic fields and coils, we suggest using the book "Fundamentals of Physics: Electromagnetism" by Halliday, Resnick, and Walker, which provides a didactic and comprehensive approach to the subject. Additionally, we recommend the Só Física website, which offers a detailed explanation of the topic and contains various exercises for practice.
Finally, we suggest watching the video "Magnetic Field of a Coil - Physics" available on the Physics University YouTube Channel, as it makes the theoretical concept tangible and is a critical source of knowledge for understanding the content.
Practical Activity: Construction and Analysis of a Coil
Project Objective
The objective of this project is to build a coil and, from it, investigate and calculate the magnetic field generated based on the current flowing through the coil and the number of turns.
The activity is structured to allow students to apply the theoretical concepts studied, promote interdisciplinarity - involving knowledge of Physics and Mathematics - stimulate teamwork, and enhance time management, communication, and problem-solving skills.
Detailed Project Description
The project will be structured in two parts: the construction of the coil (experimental part) and the theoretical analysis to calculate the magnetic field. As it is a highly complex activity involving several steps, it is estimated to take an average of 12 hours to be completed per student.
Experimental Part: Construction of the Coil
Necessary Materials:
- Enamelled copper wire gauge 28
- Aluminum foil
- Cardboard tube (can be an empty roll of paper towels)
- Adjustable power supply
- Multimeter
- Tape measure or ruler
- Magnets
Procedure:
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Wind the enamelled copper wire on the cardboard tube, ensuring that the turns are close together. The number of turns will influence the intensity of the magnetic field, so note this number.
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Connect the coil to the power supply and adjust the current passing through the coil.
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With the help of a magnet, you will be able to feel the magnetic field generated by the coil. Repeat the procedure for different currents and note the values.
Theoretical Part: Analysis and calculation of the magnetic field
Procedure:
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Based on the number of turns in the coil and the current passing through it, calculate the magnetic field created by the coil according to the Biot-Savart formula.
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Compare the values obtained experimentally with the calculated values and analyze the differences. What may have caused these differences?
Project Deliverables
At the end of the project, students must submit a complete report, covering the following main topics: Introduction, Development (which will cover the theoretical and experimental part), Conclusions, and Bibliography.
Introduction
It should contextualize the theme, its relevance and application in the real world, and the objective of this project.
Development
It should explain the theory behind the magnetic field generated by a coil, describe in detail the project steps, justify the methodology used, and present the data collected during the experiment. A critical analysis of the results obtained should also be provided, comparing the theoretical results with the experimental ones. And finally, discuss the results obtained.
Conclusion
It should recap the main points, describe the learnings obtained, the difficulties encountered during the project, and the conclusions drawn from it.
Bibliography
It should contain all sources of information used for the work, such as books, internet sites, videos, etc.
The report should be written in a clear and objective manner, addressing all the requested aspects and documenting all observations and conclusions from the experiment.
