Explaining the Infinite Reflection of a Pencil in Mirror Photography

In summary, the conversation discusses a school project involving capturing a physics phenomenon related to light and reflection. The idea of using flat mirrors placed in front of each other is proposed, and the question of how to explain the infinite reflection of a pencil placed between them is brought up. The use of ray tracing and the efficiency of each reflection is suggested, with the reminder that multiple reflections may occur from each mirror surface. The difference in reflection quality between front-surface and regular mirrors is also mentioned, and the importance of using first-surface mirrors for real physics work is highlighted.
  • #1
intimidckfan
2
0
I have a project in school in which I have to take a picture of a physics phenomenon that has to do with light and reflection. So I was thinking to use flat mirrors and put two of them in front of each other. How would I explain why the pencil I put in the middle is reflected infinitely and that it gets darker as it goes into the mirror images?
 
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  • #2
Use ray tracing and talk about the efficiency of each reflection. BTW, unless you are using front-surface mirrors, you will get multiple reflections from each mirror surface. The first (dim) one from the front surface of the glass, the second (stronger) one from the metallic reflection surface, the third (dimmer) one from the re-reflection inside the mirror back from the inside of the glass, to the metallic surface, and back out of the glass, etc.

You should talk about the difference in reflection quality in your project too. Talk about why first-surface mirrors are used for real physics work...
 
  • #3


That is a great idea for a project! Using flat mirrors to demonstrate the principles of light and reflection is a common and effective method. To explain why the pencil appears to be reflected infinitely, we must first understand how mirrors work. A mirror reflects light rays that hit its surface at an angle equal to the angle at which they approach the surface. This means that when you place two mirrors facing each other, the light rays from the pencil will bounce back and forth between the two mirrors, creating an infinite number of reflections.

As for why the pencil appears to get darker as it goes into the mirror images, this is due to the law of reflection. The law of reflection states that the angle of incidence (the angle at which the light ray hits the mirror) is equal to the angle of reflection (the angle at which the light ray bounces off the mirror). As the pencil goes deeper into the mirror images, the angle of incidence increases, causing the angle of reflection to decrease. This means that the light rays from the pencil are being reflected at a more oblique angle, making them appear darker to our eyes.

In addition, the multiple reflections also cause the light to become more diffuse, meaning that the light is scattered in different directions. This further contributes to the darker appearance of the pencil as it goes into the mirror images.

Overall, your proposed project is an excellent way to demonstrate the principles of light and reflection. I suggest experimenting with different angles and distances between the mirrors to see how it affects the appearance of the pencil in the mirror images. Good luck with your project!
 

What is a "Mirror Photography Project"?

A "Mirror Photography Project" is a type of photography project where the subject or object of the photo is reflected in a mirror. This can create unique and creative images by playing with reflections, symmetry, and perspective.

What equipment do I need for a "Mirror Photography Project"?

To do a "Mirror Photography Project", you will need a camera (a DSLR or a smartphone camera will work), a tripod (optional but recommended for stability), and a mirror (preferably a large one for more creative possibilities). You may also want to use additional props or lighting depending on your specific project.

How do I set up a "Mirror Photography Project"?

To set up a "Mirror Photography Project", first choose your subject or object and decide on the angle and composition you want to capture. Then, place the mirror in a position where it will reflect the subject or object in an interesting way. You may need to adjust the lighting and camera settings to get the desired effect.

What are some tips for taking successful "Mirror Photography Project" photos?

Some tips for taking successful "Mirror Photography Project" photos include experimenting with different angles and compositions, using natural light or adding lighting for interesting reflections, and paying attention to details in the mirror such as smudges or fingerprints.

How can I edit "Mirror Photography Project" photos?

You can edit "Mirror Photography Project" photos using photo editing software such as Adobe Photoshop or Lightroom. Some common edits for these types of photos include adjusting the contrast and color to enhance the reflections, cropping to improve composition, and removing any unwanted objects or distractions in the mirror.

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