Context

The magnetic field generated by a coil, also known as a solenoid, is a fundamental topic in physics. It has important implications in modern technologies, as well as in the fundamental description of the electromagnetic interaction. In this project, you will have the opportunity to understand the concept and application of magnetic fields in a fun and engaging way.

Essentially, a coil is an electric wire wound around a core, forming a cylindrical shape. When an electric current passes through this wire, a magnetic field is created around the coil, which is the basis for many electrical devices we use in our daily lives.

Introduction

The study of magnetic fields generated by coils is one of the fundamental pillars in the discipline of Physics. Understanding this concept enables the comprehension of how various devices and instruments that are so common in our lives work, such as the electric motor, transformer, power generator, and many others.

Such magnetic fields are governed by Ampère's Law, which allows calculating the intensity of the magnetic field at any point of a coil traversed by a current. In it, one learns that the magnetic field is directly proportional to the current passing through the wire and the number of turns that make up the coil.

Furthermore, it is important to mention Faraday-Neumann-Lenz's Law, which relates the variation of the magnetic field over time to an induced current. This law, of utmost importance, is the basis for the operation of generators and electric motors.

Now that you have a general idea of what the magnetic field is and the importance of its generation by coils, how about delving deeper into this subject?

Practical Activity

Activity Title: "Coil in Action: Exploring the Magnetic Field"

Project Objective

The objective of this activity is to allow students to understand, in practice, how a coil generates a magnetic field and how this magnetic field changes with the number of turns and the current intensity.

Detailed Project Description

Students, in groups of 3 to 5, will build a simple coil and investigate how varying the number of turns and the electric current affects the generated magnetic field. They will also compare the magnetic field generated by coils with different numbers of turns. The entire process should be properly documented, including photos and/or videos to help demonstrate and explain their conclusions.

Required Materials

• Enamelled copper wire
• A plastic or cardboard rod or tube (e.g., an empty toilet paper roll)
• A multimeter capable of measuring electric current
• Adjustable DC power supply
• Compass or a cell phone app with a compass function
• Meter paper and adhesive tape

Detailed Step-by-Step

1. Wind the copper wire around the rod or tube, forming your coil. Make sure the wire is well wound and the turns are close to each other.

2. Connect the wire terminals to the power supply and adjust the electric current initially to a low value.

3. Position the compass near the coil and observe the direction in which the needle points.

4. Increase the electric current and observe what happens to the compass needle. Record your observations.

5. Create another coil with a larger number of turns and repeat steps 2 to 4.

6. Compare the magnetic fields generated by the two coils. Discuss, within the group, the results found.

7. Each group member should individually write their conclusions and then discuss them together to reach a consensus.

Project Deliverables

Students must submit a report documenting the entire process and the conclusions. The report should include:

1. Introduction: Contextualization of the scenario, importance of the magnetic field generated by a coil, project objective.

2. Development: Theoretical explanation of the concepts involved (magnetic field, electric current, coil), detailed description of the activity performed (including photos, if possible), discussion of the results obtained.

3. Conclusion: Recap the main points, explain the acquired learnings, conclude about the project detailing which factors determine the intensity of the magnetic field.

4. Bibliography: Sources consulted (books, websites, videos).

The report will be used to evaluate both the students' theoretical knowledge and their understanding of the subject, as well as their teamwork and communication skills. Additionally, the group's time management will also be verified, considering they will have one week to complete the project.

Remember: these procedures aim at everyone's safety. Therefore, follow the instructions correctly and pay attention throughout the entire process. Good luck!