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Design and manufacturing process and precautions of cosmetic mirror

1. Plane mirror: we call a mirror whose reflection is a smooth plane a plane mirror; For example, the mirror we look at when combing our hair, the dressing mirror and the mirror hanging in the dance classroom are plane mirrors;

2. Manufacturing process (this plane mirror is composed of five bamboo sticks, five wooden strips and an aluminum foil mirror):

1) Find out the two longest wooden strips, make the two holes opposite and the other hole facing upward, and splice the two opposite holes with two bamboo sticks;

2) . insert the other two bamboo sticks into the other hole of the above two wooden strips respectively;

3) Use another bamboo stick to penetrate through the small hole of the longer wooden strip, and make the wooden strip in the middle of the bamboo stick;

4) . insert the bamboo stick in the previous step into the small hole on the side of the two remaining wooden strips (blocks) respectively, and keep the small hole on the other side of the two wooden strips downward;

5) . splice the small holes of the above two wood blocks with the bamboo stick connecting the two long wood strips;

6) . stick the double-sided adhesive to the wood block passing through the bamboo stick, stick the back of the aluminum foil mirror to the wood block, and tear off the protective film on the aluminum foil mirror.

3. Planar mirror imaging features:

1) The image is upright;

2) The image is the same size as the object, but in the opposite direction;

3) The image formed is a virtual image.

4. Application and knowledge development:

1) Flat mirrors are widely used in daily life. For example, the mirrors around the walls in the practice room and the small mirrors put into the mouth when the dentist examines the teeth are all flat mirrors; There are plane mirrors in periscopes, microscopes and projectors used by submarines. In addition, the calm water surface and polished metal surface are equivalent to plane mirrors;

2) Concepts and differences between real image and virtual image:

A. Real image: the refraction emitted by the object point through the lens, all refraction lines can converge at one point, which is called the real image point of the object point, and the collection of all real image points is called the image of the object. The characteristics of the real image are: the convergence, handstand and opposite sides of the actual light can be formed on the screen;

B. Virtual image: the light emitted by the object point is refracted by the lens, and the intersection of the reverse extension line of its refraction ray is called the virtual image point of the object point, and its collection is called the virtual image of the object. The characteristics of virtual image are: it is not the convergence of actual light, standing upright, on the same side, and can not be formed on the screen.

4、 Precautions:

1. Before making, the five wood blocks can be divided into three groups according to the size, that is, the two longer and shorter are one group respectively, and the other with holes in the middle is one group, which is more convenient for making. In addition, when splicing, pay attention to the position of small holes on each wood block;

2. After the production, the imaging characteristics of the plane mirror can be verified with the help of this experiment. If the distance between the cosmetic mirror and the object (person) is enlarged, the image presented is small but the range is large. In addition, the angle of the cosmetic mirror can be changed by rotating the wood block;

3. Real and virtual images are only for simple understanding.