Setting

In Physics, a plane mirror is a mirror with a flat surface. Most of the mirrors used in our daily lives are flat, such as bathroom mirrors, car rearview mirrors, among others. In flat mirrors, the image formed has the same size as the object, is virtual (because it can be seen by the human eye, but cannot be projected onto a screen) and is upright in relation to the object.

When a plane mirror moves relative to a fixed object, the image of this object in the mirror also moves. This is a fundamental concept for understanding our topic: Plane Mirrors in Motion. In order to fully understand this concept, it is necessary to delve into the fundamental principles of geometric optics, such as light reflection and the laws of reflection.

Importance of the Topic

Believe it or not, the physics behind moving plane mirrors has practical applications in several fields. For example, in traffic engineering and road design, the position and tilt of road safety mirrors are adjusted considering the expected speed of the vehicles. In medicine, understanding the behaviour of moving mirrors is essential for the functioning of several diagnostic instruments, such as the ophthalmoscope. Even in visual arts, this knowledge can be useful.

Practical Activity: "Motion Mirroring"

Purpose of the Project

The aim of the project is to study and observe the concept of "Plane Moving Mirror", by analysing the propagation velocity of the image formed when a mirror moves relative to a fixed object. Students will work in groups of 3 to 5 people, and the project will extend over a month.

Project Details

The project is to conduct a controlled experiment to measure the velocity of propagation of an image when a plane mirror moves in relation to a fixed object. Students will need to carry out a series of experiments, collect and analyse data, and then formulate conclusions based on their observations.

Necessary Materials

• Small plane mirror
• Measuring tape
• Camera or smartphone to record the experiment
• Tape measure
• Marker pen

Step-by-Step Instructions for Activities

1. Find a suitable location to carry out the experiment.
2. Position the mirror in a fixed position and mark the positions of the object and the mirror.
3. Move the mirror towards the object and use the camera or mobile phone to record the experiment.
4. Perform this operation several times, each time at a different speed.
5. Now, analyse the videos. Observe how the image of the object in the mirror moves when you move the mirror.
6. Use the data obtained to calculate the velocity of propagation of the image.
7. Discuss and analyse the results as a group to understand the behaviour of the object's image when the mirror moves.

Project Deliverables

The activity will end with the preparation of a report on the experiment, which will include:

1. Introduction: The student should contextualize the topic, its real-world relevance and application, and the aim of the project.

2. Development: The student should explain in detail the theory behind the phenomenon of the "moving plane mirror", explain the experiment in detail, indicate the methodology used, and finally present and discuss the results obtained. The analyses of the videos should also be included in the development.

3. Conclusion: The student should conclude the work by returning to the main points, outlining what was learned and the conclusions drawn from the experiment. Improvements to future experiments and practical applications of the concept studied can also be discussed here.

4. Bibliography: The student should indicate the sources used as the basis for the work on the project, such as books, websites, videos, etc.

Students should submit the report (PDF format), as well as the videos of the experiments conducted. Make sure the report is clear, professional and reflects what you learned during the project.