Contextualization

The study of resistors and the different ways they can be associated represents one of the fundamental pillars of electronics. Found in virtually every electronic device, ranging from simple light switches to complex computers, resistors are essential components for controlling electrical currents.

Resistors can be combined in several ways to achieve specific functions, with series and parallel associations being the most common. However, these are not the only association modes, and in many real-world circuits, we find more complex resistor arrangements, demanding a deeper understanding of electrical theory.

Introduction to Resistors and Associations

Resistors are electronic components that are used to limit the amount of electrical current flowing through a circuit; they are characterized by their electrical resistance, a quantity that quantifies how much the resistor "resists" the passage of current. Electrical resistance is measured in ohms, symbolized by Ω.

When we have more than one resistor in a circuit, we can connect them in different ways, establishing what we call resistor associations. These associations can be of two basic types: series or parallel. In more complex circuits, resistors can be connected in mixed associations.

Importance and Applications in the Real World

The ability to work with resistor associations is a crucial skill for anyone working in electronics or electricity. This is because resistors are used in practically every electronic device. TVs, computers, phones, cars, airplanes, satellites... All of these devices and many more contain resistors in their circuits.

Moreover, understanding resistor associations contributes to a better comprehension of electricity and the world around us. Since electricity is one of the most used forms of energy by modern society, knowing the principles that govern its use is fundamental.

Practical Activity

Activity Title: Resistor Circuit Construction and Analysis

Project Objective

This project aims to construct an electrical circuit with resistors in different association configurations, measure the currents and voltages at strategic points of the circuit, and compare the results with electrical circuit theory. This activity will provide an opportunity to work in teams, apply theory to practice, and develop problem-solving skills.

Detailed Project Description

The groups, composed of 3 to 5 students, will design and build a circuit using at least 10 resistors, organized in different types of associations (series, parallel, and mixed). The circuit must be powered by a DC voltage source (battery or adjustable power supply).

After the circuit is built, the group will measure voltages and currents at different points of the circuit using a voltmeter and an ammeter, respectively.

The experimental results obtained will be compared with theoretical calculations, which should be done beforehand considering the nominal values of the resistors and the voltage of the source.

Required Materials

• Resistors of different values
• Connecting wires
• Breadboard
• DC voltage source (battery or adjustable power supply)
• Voltmeter
• Ammeter

Detailed Step-by-Step for the Activity

1. Form groups of 3 to 5 students.
2. Sketch the circuit you want to build, including at least 10 resistors organized in different types of associations (series, parallel, and mixed).
3. Perform the theoretical calculations of the expected voltage and current values at different points in the circuit.
4. Build the circuit according to the sketched schematic, taking care to connect all components correctly.
5. Connect the power supply to the circuit.
6. Use the ammeter and voltmeter to measure the currents and voltages at different points of the circuit.
7. Record all measurements made.
8. Compare the measurements with the theoretical calculations performed earlier.

Project Deliverables

At the end of the project, the groups must submit a written report containing the following sections:

1. Introduction: Each group must contextualize the topic of resistor association and its importance. This is the space to indicate the relevance of the activity and what is expected to be learned from it.
2. Development: In this section, the group should describe in detail the theory involved in resistor association and how it was applied in the project. The practical activity should be explained in detail, indicating the methodology used, presentation, and discussion of the results obtained.
3. Conclusions: The group should conclude the work by going back to the main points, explaining what they have learned, returning to the project's objective, and discussing the conclusions obtained about the work. A self-criticism about the execution of the project should also be included, revealing what difficulties were faced and how they were overcome.
4. Bibliography: The group should indicate the sources used to carry out the project, including books, web pages, videos, etc.

This report should be written clearly and objectively and should contain, in addition to text, images of the assembled circuit and the schematics used, comparative tables between the calculated and measured values, and graphs (if applicable).