Lesson plan of Waves: Refraction

Objectives (5 - 7 minutes)

1. Understand the concept of wave refraction: The teacher will introduce the students to the concept of wave refraction, explaining that it is the phenomenon that occurs when a wave passes from one medium to another, changing its speed, direction and wavelength. Students should understand that refraction occurs due to the change in the wave velocity in the different media.

2. Identify the laws of refraction: The teacher will teach the students the laws of refraction, which are the mathematical relationships that govern the behavior of a wave when passing from one medium to another. Students should be able to identify and apply these laws in practical situations.

3. Solve problems involving wave refraction: The teacher will propose some problems for the students to solve, in order to apply the concepts and laws of refraction. Students should be able to identify relevant information, formulate the correct equation and arrive at the solution of the problem.

Secondary Objectives:

• Develop critical thinking and problem solving skills: By solving the proposed problems, students will be encouraged to think critically and develop problem-solving skills, which is fundamental in the study of Physics.

• Promote interaction and teamwork: The teacher should encourage interaction between students, promoting discussions and group activities, in order to promote teamwork and the exchange of ideas and experiences.

Introduction (10 - 12 minutes)

1. Review of previous content: The teacher should begin the class by briefly reviewing the concepts of waves and their characteristics (amplitude, frequency, period, velocity, etc.), which were studied in previous lessons. This review can be done through questions directed to the students, in order to check their level of understanding of the subject (3 - 4 minutes).

2. Presentation of problem situations: The teacher should present two problem situations that involve the phenomenon of refraction. The first situation could be the explanation of why a spoon appears to be broken when immersed in a glass of water. The second situation could be the explanation of the phenomenon of rainbow formation. The teacher should ask the students how they believe these situations relate to the concept of refraction (3 - 4 minutes).

3. Contextualizing the importance of the subject: The teacher should explain to the students the importance of studying refraction, citing some practical applications, such as the formation of images in lenses, the propagation of sound in air and the formation of rainbows. The teacher could also mention that refraction is a phenomenon that occurs constantly in our daily lives and is essential for the functioning of various devices, such as glasses, microscopes, telescopes, among others (2 - 3 minutes).

4. Introduction of new content: Finally, the teacher should introduce the new content, explaining that in today's class the students will learn about the phenomenon of wave refraction and the laws that govern it. The teacher should draw the students' attention to the importance of understanding and applying these laws, since they are fundamental to the understanding of several natural phenomena and for the development of several technologies (2 - 3 minutes).

Development (20 - 25 minutes)

1. Experimentation Activity: "Refraction in Practice" (10 - 12 minutes)

   • Preparation: The teacher should prepare in advance a transparent glass tray, water, a pencil and a piece of paper. The teacher will fill the glass tray with water, until it is almost full. Next, the teacher will place the pencil on the edge of the tray, so that part of the pencil is in the water and another part outside. Finally, the teacher will position the paper in front of the tray, so that the students can see the pencil through the water.

   • Execution: The teacher will ask a student to observe the pencil through the paper and write down what he sees. Then, the teacher will tilt the glass tray so that the pencil appears to be bent. The teacher will ask the students what they observed and what they think caused this change in the appearance of the pencil. The teacher will then explain that what the students observed is the phenomenon of refraction, and that the change in the appearance of the pencil is due to the refraction of light passing from the water to the air.

   • Discussion: The teacher will lead a discussion with the students about the experiment, asking them what they learned from the activity and how they believe it relates to the concept of refraction. The teacher should reinforce the idea that refraction occurs when light passes from one medium to another, and that it is responsible for various phenomena that we observe in everyday life.

2. Playful Activity: "The Rainbow Challenge" (10 - 12 minutes)

   • Preparation: The teacher should prepare in advance a prism, a flashlight and a piece of white paper. The teacher will position the prism so that the sunlight or the flashlight shines on it, and the white paper so that the students see the rainbow that will form.

   • Execution: The teacher will ask a student to hold the flashlight and point it at the prism, so that the light strikes it. Then, the teacher will ask another student to observe the rainbow that will form on the white paper. The teacher will ask the students what they observed and what they think caused the formation of the rainbow. The teacher will then explain that what the students observed is the phenomenon of light refraction, and that the formation of the rainbow is due to the refraction of sunlight in water droplets present in the air.

   • Discussion: The teacher will lead a discussion with the students about the experiment, asking them what they learned from the activity and how they believe it relates to the concept of refraction. The teacher should reinforce the idea that the refraction of light is responsible for the formation of the rainbow and many other phenomena that we observe in everyday life.

3. Practical Application Activity: "Solving Refraction Problems" (5 - 7 minutes)

   • Preparation: The teacher should prepare in advance some problems involving the phenomenon of refraction. The problems can involve determining the angle of refraction of a wave passing from one medium to another, determining the refractive index of a medium, among others.

   • Execution: The teacher will propose a problem for the students to solve in groups. Students should identify relevant information, formulate the correct equation, and arrive at the solution to the problem.

   • Discussion: The teacher will lead a discussion with the students about solving the problem, asking them how they arrived at the solution and if they have any questions. The teacher should reinforce the importance of understanding and correctly applying the laws of refraction to solve the problems.

Feedback (8 - 10 minutes)

1. Group Discussion (3 - 4 minutes): The teacher should gather all students in a circle for a group discussion. He should ask the students what they learned from the practical activities carried out and how they believe that these activities relate to the concept of refraction. The teacher should also ask the students if they can think of other everyday situations where the phenomenon of refraction occurs. The purpose of this discussion is to check whether the students were able to apply the concepts and laws of refraction in interpreting the observed phenomena and solving the proposed problems.

2. Connection with Theory (2 - 3 minutes): After the discussion, the teacher should make the connection between the practical activities performed and the theory studied. He should explain again the concept of refraction, the laws of refraction and how they were applied in the activities. The teacher should reinforce the idea that refraction is a phenomenon that occurs when a wave passes from one medium to another, and that it is responsible for various phenomena that we observe in everyday life. He should also reinforce the importance of understanding and correctly applying the laws of refraction to solve the problems.

3. Individual Reflection (2 - 3 minutes): The teacher should ask the students to individually reflect on what they learned in class. He should ask the following questions: "What was the most important concept you learned today?" and "What questions do you still have on the subject?" The students will have one minute to think about the questions and then they should share their answers with the group. The teacher should write down the students' responses and use them to plan upcoming lessons to ensure that all questions are clarified and concepts are solidified.

4. Teacher Feedback (1 minute): Finally, the teacher should give general feedback on the students' participation and performance in class. He should praise the positive aspects, such as active participation, collaboration and correct problem solving. He should also point out aspects that need to be improved, such as attention to detail, equation formulation and logical argumentation. The teacher should encourage students to continue studying and practicing what they learned in class, and to seek him out whenever they have questions.

Conclusion (5 - 7 minutes)

1. Summary and Recapitulation (2 - 3 minutes): The teacher should summarize the main points covered in class, reinforcing the concept of refraction, explaining the laws of refraction, and how these laws were applied in the practical activities. He should recap the problem situations presented in the Introduction and how they were solved with the knowledge acquired. The teacher should also recall the practical applications of refraction, such as the formation of images in lenses, the propagation of sound in the air and the formation of rainbows.

2. Connection of Theory with Practice (1 - 2 minutes): The teacher should explain again how the class connected theory with practice. He should emphasize that the purpose of the practical activities was to allow the students to observe and experience the phenomenon of refraction, and that the purpose of the discussion was to allow the students to apply the theory in interpreting the observed phenomena.

3. Complementary Materials (1 minute): The teacher should suggest some materials for the students to study more about the subject. These materials may include Physics books, educational websites, explanatory videos, among others. The teacher should emphasize that autonomous study is essential for the understanding and fixing of concepts.

4. Importance of the Subject (1 - 2 minutes): Finally, the teacher should explain the importance of studying refraction. He should mention again the practical applications of this phenomenon, such as the formation of images in lenses, the propagation of sound in the air and the formation of rainbows, and how the understanding of these applications can contribute to the development of various technologies. The teacher should also emphasize that refraction is a phenomenon that occurs constantly in our daily lives, and that its study allows us to better understand the world around us.