Magnetic Field: Coil | Socioemotional Summary

Objectives

1. Understand the basic principles of the magnetic field generated by a coil.

2. Calculate the magnetic field generated by coils in different practical situations.

3. Develop skills to solve problems involving calculations of magnetic fields from coils.

Contextualization

Have you ever wondered how magnetic resonance works that doctors use to see inside our body? Or how that old fan at home can keep spinning during hot days?  All this is possible thanks to the magnetic field generated by coils!  Let's explore together how this magic of physics applies to our daily lives and allows us to live more comfortably and healthily. 

Important Topics

Magnetic Field

The magnetic field is a field of force generated by moving electric charges. When electric current passes through the wires of a coil, it creates a magnetic field around them. This field can be visualized as lines of force extending from one pole to the other of the coil, similar to the lines surrounding a magnet.

• Definition of Magnetic Field: A force field created by moving electric charges.

• Field Lines: Magnetic field lines show the direction and strength of the field around the coil. The closer the lines are, the stronger the field is.

• Polarity: Just as a magnet has North and South poles, a coil also creates magnetic poles when electric current flows through it.

Ampère's Law

Ampère's Law is one of the main laws of electromagnetism and allows the calculation of the intensity of the magnetic field around a conductor. For a coil, this law is used to determine the relationship between the current flowing through the wires and the magnetic field generated around it.

• The Concept: Ampère's Law states that the closed integral path of the current density along a circuit is proportional to the total magnetic flux through the surface it encloses.

• Formula: The mathematical expression of Ampère's Law is ∮B·dl = μ₀I, where B is the magnetic field, dl is the infinitesimal element of the path, μ₀ is the permeability of free space, and I is the current.

• Application: Using Ampère's Law, we can calculate the intensity of the magnetic field inside and outside a coil, allowing for a deeper understanding of electromagnetic behavior.

Coil

A coil is a conductor wire wound in a spiral, and its design is crucial for creating strong and controlled magnetic fields. The number of turns of the coil, the electric current passing through it, and its length are factors that directly influence the generated magnetic field.

• Structure: The coil is essentially a conductor wire wound into a cylindrical shape, allowing the current to pass through multiple turns.

• Number of Turns: The more turns the coil has, the stronger the generated magnetic field will be.

• Electric Current: The intensity of the electric current passing through the coil also directly affects the strength of the magnetic field.

Key Terms

• Magnetic Field: A force field resulting from the movement of electric charges.

• Ampère's Law: A fundamental law of electromagnetism that relates electric current to the magnetic field.

• Coil: A conductor wire wound in a spiral, used to generate magnetic fields.

To Reflect

• How did you feel when solving complex problems in a group? Were you able to express those emotions effectively with your colleagues?

• Did you face any frustration during the activities? How did you deal with those feelings and what strategies did you use to stay calm and focused?

• In what way can understanding the magnetic fields generated by coils change your perception of the technology we use daily?

Important Conclusions

• Today we explored the essential principles of the magnetic field generated by coils. We understood how electric current creates a magnetic field as it passes through the wires of a coil and how Ampère's Law helps us calculate the intensity of this field.

• We discussed the formula B = (μ₀ * N * I) / L, which explains the relationship between the magnetic field, the number of turns of the coil, the current, and the length of the coil.

• Through practical activities, we applied this knowledge to solve real problems, developing mathematical skills and problem-solving abilities in teamwork.

Impact on Society

Understanding the magnetic field generated by coils has a significant impact on our society. In daily life, we use electric motors in various essential devices, such as fans and blenders, whose operation directly depends on these principles. Additionally, advanced medical technologies, such as magnetic resonance imaging, rely on the magnetic fields generated by coils to provide accurate diagnoses and save lives. 

Dealing with Emotions

To help you cope with your emotions while studying magnetic fields and their applications, we propose an exercise based on the RULER method. First, recognize your feelings when facing challenges in studying, such as frustration or excitement. Try to understand the causes of these emotions and name them correctly. Then, express how you feel, whether by talking with colleagues or writing in a study journal. Finally, practice strategies to regulate these emotions, such as deep breathing or taking short breaks during study sessions. This will help maintain emotional balance and focus! 

Study Tips

• Establish a regular study routine, dedicating specific time to review concepts and solve exercises on magnetic fields and coils.

• Form study groups with colleagues to discuss problems and share different methods of resolution, promoting collaborative and effective learning.

• Use visual resources, such as drawings and animations, to better understand the magnetic field lines and how they behave around a coil.