Why do the images in a plane mirror reflect left and right but not up and down?

The principle of plane mirror imaging is the reflection of light. The light emitted from the object shines on the plane mirror, is reflected by the plane mirror and then emitted. What the human eye sees against the reflected light is the virtual image of the object. Experiments show that the object The image formed in a plane mirror is equal in size to the object, the distance between the image and the object to the mirror is equal, and the line connecting the image and the object is perpendicular to the mirror. And the left and right are opposite, and the front and back are reversed. This is the characteristic of plane mirror imaging.

Since the distance from the front and back of the object to the mirror is not equal, the image and the object are bound to be reversed. However, left and right are opposite and up and down remain unchanged, which is purely a matter of reference. Up and down are geographical directions, and the reference object is the earth. Pointing to the center of the earth means downward, and vice versa means upward. Taking a person as an example, standing in front of a vertical plane mirror, according to the characteristics of the plane mirror's image, when the head is far away from the center of the earth, its image is also far away from the center of the earth, and when the feet are close to the center of the earth, its image is also close to the center of the earth, so the position relative to the earth is constant. Left and right are relative to a specific object. Taking a person as an example, standing in front of a vertical plane mirror, according to the imaging characteristics of the plane mirror, the image of the right hand is on the right side of the person, and the image of the left hand is on the left side of the person. There is no flipping. . However, when looking at the left and right sides of the image, the image is used as a reference, and the image and the person are reversed. Therefore, the image of the person's right hand is on the left side of the image, and the image of the left hand is on the right side of the image.

I don’t know if I explain it clearly, so I’ll end it with a joke. A young man bought a new electric bicycle and rode it into a small alley. He came face to face with an old man riding an electric tricycle. They collided with each other. The old man hurriedly shouted: Hurry up, you keep to the left and I keep to the left. right. As a result, it took the two of them a long time to get up.

There are two types of judgments that people think about each other, fixed direction and changeable direction. The two different methods of judging the direction are used as one method for you to judge, which will lead to your misjudgment. Confusing.

In daily life, east, west, south, north, up and down are fixed, but front, back, left, right, and right change as people move.

For example: Someone asks you, what is the equivalent of three pounds of apples plus ten peaches? If you answer how many kilograms or how many pounds are wrong, you can answer how much.

According to the standing direction, change the left and right to east-west or north-south, and change the front and back to front and back. If you look at it again, the opposite phenomenon will not appear.

For example, there is a mirror on the south wall. If you stand in front of the mirror, right? The upper side of the body is up, the lower side is down, the east side is east, and the west side is west. The front side is the front side, and the back side is invisible.

A brief discussion

A plane mirror is the reflection of light. Since it is reflection, it must have its own characteristics. It is just a basic physical optical phenomenon. If a scientific explanation is needed, it is estimated that not many people will understand it.

The self in the mirror is not your twin brother and sister opposite you. It is the mirror that reflects your light. It will not change your direction or arrangement, but it is opposite you visually. You can If your left hand touches your left hand, you will never be able to touch it, because it is just a reflection of your light. Because the mirror is flat, it reflects faithfully and is a truly faithful tool. It is not intelligent. In addition to direct reflection, it will not study or change other visual directions of your light, nor will it beautify or uglify you. .

Thank you, I believe everyone has a mirror, an object that is both ordinary and wonderful. Your left hand is still your left hand, you can stick to the other person, your right hand is still your right hand, your head is still your head, isn't it great?

Thank you for sharing!

When you lie down on your right side, up and down = left and right.