Contextualization

The magnetic field, something we cannot see or touch, but that is constantly present in our daily lives, is one of the main tools that allow us to expand our understanding of the universe. In this project, we will specifically explore the magnetic field generated by a conductor wire carrying an electric current.

The theoretical basis of this phenomenon is the Biot-Savart Law, which describes how an electric current produces a magnetic field around it. According to this law, the magnetic field produced by a certain current element is directly proportional to the product of the current by the length element, being inversely proportional to the square of the distance from the point to the current element.

Importance of the Topic

Understanding the magnetic field generated by conductor wires is fundamental in many technological applications, from electric motors, through power generators, to medical imaging equipment, such as Magnetic Resonance Imaging. Magnetic forces act in various ways in such devices, and understanding how these forces are created and how they behave is essential for the understanding and advancement of these technologies.

Furthermore, this topic is deeply rooted in various fundamental concepts of physics and electromagnetism. Its understanding is therefore essential for the education of any student in exact sciences or engineering. In addition to its theoretical and practical relevance, the topic also offers an excellent opportunity to develop skills such as problem-solving, teamwork, and critical thinking.

Practical Activity

Activity Title: Measuring the Magnetic Field of a Conductor Wire

Project Objective

The objective of this project is to experimentally measure the magnetic field generated by a straight wire conducting current, verify its dependence on the wire's distance, and compare the experimental results with the theoretical prediction provided by the Biot-Savart Law.

Detailed Project Description

Groups, composed of 3 to 5 students, should set up an experiment to measure the magnetic field at different points around a straight wire conducting a constant electric current. They must develop a work plan, effectively dividing tasks among members, and ensure efficient communication among all.

Students will need to use concepts of Physics and Mathematics to interpret the results and compare them with what is predicted by the theory. It is essential that they demonstrate an understanding of the theory, the ability to design and conduct the experiment, and the capacity to analyze and interpret the data obtained.

Required Materials

• Straight and long conductor wire
• Power supply capable of providing a constant current
• Voltmeter and ammeter
• Magnetic field sensor
• Ruler or measuring tape
• Support for the wire and the sensor

Step-by-Step for Activity Execution

1. Set up the circuit with the current source, the straight wire, and the ammeter to measure the current passing through the wire.
2. Position the magnetic field sensor at a known distance from the wire and measure the magnetic field.
3. Repeat the measurement for different distances from the wire.
4. Collect the experimental data and create a graph of the magnetic field as a function of distance.
5. Use the Biot-Savart Law to calculate the magnetic field as a function of distance and compare the theoretical results with the experimental ones.

Project Deliverables

Students must submit a written report in the form of a scientific article containing the following topics:

1. Introduction: Provide context for the topic, its relevance, real-world applications, and the objective of this project.
2. Development: Explain the theory (including the Biot-Savart Law), the activity in detail, the methodology used, and present and discuss the results obtained (using graphs and tables when necessary). What were the difficulties encountered during the experiment? How were they solved?
3. Conclusion: Conclude the work by summarizing its main points, explaining the learnings obtained, and drawing conclusions about the project. Are the experimental results in line with the theoretical prediction? Why or why not? What does this tell us about the Biot-Savart Law?
4. Bibliography: Indicate the sources of information used for the project's development.

Students must also present the experiment to the class, explaining the procedure and discussing the results obtained. This presentation should be brief but precise and informative, encouraging interaction with classmates and fostering collaborative learning.