Hotel two-way mirror

Some small hotels have this situation, and the identification method is as follows:

Turn on the flashlight of our mobile phone and put it close to the mirror. When you look in the mirror, you will see your true self in the mirror, which proves that this is an ordinary mirror.

If you can't see yourself, it means that this is a double mirror. At this time, we can see that the mirror is not hollow by knocking on it with our hands. If it is hollow, it means that a camera is probably installed here. If it is solid, it will not expose our privacy.

Extended data:

Whether it is a flat mirror or a non-flat mirror (concave mirror or convex mirror), light will obey the law of reflection and be reflected by the flat mirror, and the reflected light can form vision in the retina after entering the eyes.

On a flat mirror, a parallel beam hits the mirror, and the whole body changes direction in a parallel way. At this time, the imaging is the same as what the eyes see.

Mirrors and scales are tools to measure a woman's figure. For example, when a woman weighs herself with a scale, she knows whether she is fat or thin. However, as women's cognition of beauty becomes more intuitive and concrete, mirrors gradually replace the role of scale here. Therefore, "replacing the scales at home with mirrors" is the slogan for more women to test their beauty.

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