Objectives (5 - 7 minutes)

1. Understand the concept of electric power: The teacher must ensure that students understand what electric power is, how it is calculated, and how it relates to electric current and potential difference.

2. Apply the formula for electric power in practical problems: Students should be able to use the formula for electric power (P = V x I) to solve problems involving the calculation of electric power, electric current, or potential difference.

3. Differentiate between power, energy, and electric work: Students must understand the difference between these related concepts and be able to apply each of them correctly in specific contexts.

   Secondary objectives:

   • Develop problemsolving skills: Through practice of calculations involving electric power, students should enhance their problemsolving skills.

   • Stimulate curiosity and critical thinking: The teacher should encourage students to think about how electricity is used in their daily lives, and how electric power applies to these uses.

Introduction (10 - 15 minutes)

1. Review of previous concepts: The teacher should start the lesson by reviewing fundamental concepts that are prerequisites for the current topic. This may include a quick review of electric current, potential difference, and the relationship between them. The teacher may ask students questions to verify their understanding of these concepts. This step is crucial to ensure that all students are on the same page and ready to learn about electric power.

2. Initial problem situations: The teacher can present two problem situations to arouse students' interest and show the relevance of the topic. For example:

   • Situation 1: 'Imagine you have two electronic devices, a hairdryer and a cell phone charger. Both are plugged into the same outlet, but the hairdryer is much more powerful. How does this affect the time needed to charge the cell phone?'

   • Situation 2: 'If you have an electric circuit with a 9-volt battery and a 3-watt light bulb, how long will the bulb remain lit before the battery runs out?'

   The teacher should encourage students to think about these situations and make assumptions before explaining the concepts of electric power.

3. Contextualization of the subject's importance: The teacher should explain that electric power is a fundamental concept for understanding how electricity is used in our daily lives. He may mention examples of devices we use regularly and how electric power is crucial in determining their performance and efficiency.

4. Introduction to the topic: To grab students' attention, the teacher can share some curiosities or interesting applications of the topic. For example:

   • Curiosity 1: 'Did you know that electric power is measured in watts, in honor of James Watt, the inventor of the steam engine? He was one of the first to understand the relationship between power, work, and time.'

   • Curiosity 2: 'Here's a surprising fact: the world's largest hydroelectric power plant, the Three Gorges Dam in China, has an installed power of 22,500 megawatts, which means it can provide enough energy for a city of 10 million people!'

   The teacher should ensure that students are engaged and curious about the topic before moving on to the theoretical part of the lesson.

Development (20 - 25 minutes)

1. Simulation Activity (10 - 12 minutes):

   • The teacher should divide the class into small groups and provide each group with a 'simulation kit' consisting of a 9-volt battery, an LED light bulb, connection wires, and a digital multimeter.

   • The teacher should explain that the LED bulb has a nominal power of 3 watts and that the battery provides a potential difference of 9 volts. The goal of the activity is to determine how long the bulb will remain lit before the battery runs out.

   • Students should measure the current passing through the bulb using the multimeter and then use the formula for electric power (P = V x I) to calculate the actual power being used by the bulb.

   • Once students have calculated the power, they can divide the power by the nominal power of the bulb to determine the fraction of time the bulb will remain lit before the battery runs out.

   • Students should record their calculations and observations, and then compare the results with the predictions they made at the beginning of the activity. The teacher should circulate around the room, providing guidance and clarifying doubts as needed.

2. Discussion Activity (5 - 7 minutes):

   • After the conclusion of the simulation activity, the teacher should gather the students and lead a discussion about the results. He should ask students what they learned from the activity and how it relates to the concept of electric power.

   • The teacher should emphasize that electric power is the rate at which electric energy is transferred or converted, and that power is directly proportional to electric current and potential difference.

   • The teacher can use the simulation activity as a concrete example to illustrate these concepts. For example, he can ask students how the power (and therefore the brightness of the bulb) would change if they used a battery with a higher or lower potential difference, or if they connected multiple bulbs in series or parallel.

3. Practical Activity (5 - 6 minutes):

   • To conclude the Development stage, the teacher should propose a practical problem for students to solve in their groups. For example, 'If a device has a power of 1000 watts and is connected to an outlet with a potential difference of 120 volts, what will be the electric current passing through the device?'

   • Students should use the formula for electric power to solve the problem. The teacher should circulate around the room, observing the progress of the groups and offering help as needed.

   • After a set time, the teacher should ask a representative from each group to present their solution and explain their reasoning. The teacher should provide constructive feedback and correct any conceptual errors that may have been made.

Return (8 - 10 minutes)

1. Group Discussion (3 - 5 minutes): The teacher should gather all students and promote a group discussion. Each group should share their solutions or conclusions from the activities performed. This will allow students to learn from each other, see different approaches to the same problem, and reinforce what they have learned. During the discussion, the teacher can ask questions to stimulate critical thinking, such as:

   • 'Why did you choose this strategy to solve the problem?'
   • 'How would you apply these concepts in a real-life situation?'

   The goal is not only to check students' understanding but also to encourage reflection and connection between theory (concept of electric power) and practice (calculations and activities performed).

2. Learning Verification (2 - 3 minutes): After the group discussion, the teacher should briefly review the key concepts covered during the lesson. He can ask students to explain in their own words what electric power is, how it is calculated, and why it is important. The teacher can also propose a review question, such as:

   • 'If a device has a power of 500 watts and is connected to an outlet with a potential difference of 100 volts, what will be the electric current passing through the device?'

   The goal is to verify if students can apply the concepts learned to solve similar problems. The teacher should encourage all students to participate and offer positive feedback to reinforce learning.

3. Individual Reflection (2 - 3 minutes): To conclude the lesson, the teacher should propose that students reflect individually on what they have learned. He can ask questions like:

   1. 'What was the most important concept you learned today?'
   2. 'What questions have not been answered yet?'

   This will give students the opportunity to consolidate their learning and identify any areas that may need further study or clarification. The teacher can ask students to write their answers on a piece of paper or share them verbally. The teacher should emphasize that there are no right or wrong answers and that the goal is to promote self-assessment and awareness of learning.

4. Homework Assignment (Optional): If time allows, the teacher can propose a homework assignment to reinforce the concepts learned. For example, students may be asked to research and report on an electronic device of their choice, including the power, current, and potential difference required for its operation. This will not only help consolidate students' understanding of electric power but also encourage curiosity and independent research.

Conclusion (2 - 5 minutes)

1. Summary of Contents (1 - 2 minutes): The teacher should start the Conclusion by summarizing the main points covered in the lesson. This includes the concept of electric power, the formula to calculate it (P = V x I), and the relationship between power, current, and potential difference. He should reinforce that power is the rate at which electric energy is transferred or converted, and that it is measured in watts.

2. Connection between Theory and Practice (1 minute): The teacher should explain how the lesson connected theory and practice. He can mention the simulation and group discussion activities, where students had the opportunity to apply theoretical concepts in practice. He can also highlight how the practical activity helped reinforce students' understanding of electric power.

3. Extra Materials (1 minute): The teacher should provide suggestions for extra materials for students who wish to deepen their understanding of the topic. This may include recommended readings, educational videos, interactive websites, or simulation apps. He can also suggest additional problems for students to solve at home, to practice calculating electric power.

4. Relevance of the Subject (1 minute): Finally, the teacher should emphasize the importance of the subject for students' daily lives. He may mention again examples of how electric power is applied in everyday situations, such as the operation of electronic devices, and how understanding this concept can help students make more informed decisions about electricity use. He should encourage students to remain curious and continue exploring the world of electricity, even after the end of the lesson.