You may have seen a viral video on TikTok where someone put a piece of paper on a mirror and then placed an egg against the paper. When he looked from the side, the mirror was showing the egg despite the fact that there was a non-see-through paper between the egg and the mirror. How is this possible? How can a mirror show objects that it doesn’t have a direct line of sight of?
To understand this phenomenon, we need to know how mirrors work. A mirror is an object that has a smooth surface, usually glass, coated with a metal that reflects light. When light hits the mirror, it bounces back at the same angle as it came. This creates an image of whatever is in front of the mirror, but reversed. The image is clear because the mirror does not disrupt the light. The mirror needs light to reflect, otherwise it is dark. The light can come from different sources, such as the sun, a lamp, or even another mirror.
How Does the Mirror Know That There’s an Object There?
Now that we know how mirrors and light work, let’s see how a mirror can reflect objects that are not directly visible to it. In the viral video the person has a piece of paper on a mirror, and put an egg against the paper. When they look from the side, you can see the egg reflected in the mirror despite the fact that there is a non-see-through paper between the egg and the mirror. How is this possible?
The answer is that light can bend around corners and edges. This phenomenon is called diffraction. When light waves encounter an obstacle or a slit, they can bend or spread out and continue their path. The amount of bending depends on the wavelength of the light and the size of the obstacle or slit.
In the video, when light from the egg hits the edge of the paper, some of it bends around the paper and reaches the mirror. The mirror then reflects this light back to your eyes, creating an image of the egg. The image may be distorted or blurry, because not all of the light from the egg reaches the mirror or your eyes.
You can try this experiment yourself with different objects and see what happens. You can also use other reflective surfaces besides mirrors, such as water or metal. Here is a graphical representation of what is happening in the footage.
In conclusion, mirrors are fascinating objects that can show us images of ourselves, and other things that are in front of them. Mirrors work by reflecting light at the same angle as it came. Mirrors can also reflect objects that are not directly visible to them by using diffraction, which is when light bends around corners and edges. They don’t have any special power to “know” something is there.