The candle burns shorter and shorter, and the image of the candle flame on the light screen moves up

Because it is a small hole imaging.

principle, so when the height of the flame decreases after the candle becomes shorter, the light passes through the small hole according to the similar triangle.

The image of the knowledge that can be formed will move upwards.

The candle burns shorter and shorter, and the image of the candle flame on the light screen moves towards **. On the light screen, the image of the candle flame moves upwards. Take the light emitted by a little point on the tip of the candle flame, and propagate it in a straight line through the convex lens center or small hole, and the position on the light screen will gradually move upwards as the candle flame becomes shorter.

The same is true for the whole candle flame principle.

The candle burns shorter and shorter, and the main actor on the light screen looks like an upward one. Because the candle smoke moved downward. So its elephant needs to move upwards.

Because the light can jump on the wall, and the direction of the light is different each time it is brushed, it feels like he is moving.

15.As shown in Figure 10, the focal length of the convex lens is 10cm, and the candle forms a letter on the light screen at this timeResistance 10-||The correct one is ()aIf the candle burns shorter, the image of the candle flame on the light screen will move downwards -||b.

If the candle moves away from the convex lens, the image of the candle flame will gradually become larger-||c.If you keep the position of the convex lens still and swap the position of the candle and the light screen, you can get an inverted and reduced real image on the light screen, -|Imaging rules can be applied to camera-||d.If you keep the candle and the light screen still, and move the lens to the right, you may form an inverted handstand on the light screenEqual size like -||

Because the candle burns through a convex lens to form an inverted image on the screen, the shorter the candle, the more upward the image.

Why candles are getting shorter and shorter.

The candle burns the particles formed by the candle, which means that the white smoke is blown out, why does the candle become shorter after burning? Wax to **?

I know the chemistry answers, I don't know if you need them.

The candle burns shorter (it ran to **?) ）

Hello! First of all, let's look at the composition of the candle: the composition of the candle and its combustion product, the candle is usually made of paraffin wax.

Paraffin wax is produced from the waxy fraction of petroleum by cold pressing or solvent dewaxing. Paraffin is a mixture of several higher-order alkanes, mainly n-dodo-two (C22H46) and n-octadecane (C28H58), containing about 85 carbon elements and about 14 hydrogen elementsStearic acid (C17H35COOH) is often added to the top candle to improve softness.

When the candle is burned, the products of the combustion of n-docadecane and stearic acid are carbon dioxide and water, so the candle burns shorter, and it becomes carbon dioxide and water into the air!

When doing experiments, what are the consequences of the candle becoming shorter, and what measures can be taken.

The light is straight, the middle lens is unchanged, and the candle on the right moves downward, so the image on the left light screen moves up, and the main optical axis is assumed to be horizontal.

Do experiments, what are the consequences of the gradual shortening of the candle, what measures can be adopted.

Under. Below the main optical axis.

Originally, the main optical axis and the center of the optical screen were on the same horizontal line, but now the main optical axis is lower. Along the line of the center of the light screen, the center of the convex lens, the candle is below the main optical axis.

There is a light that passes through the center of light, the direction of propagation does not change, the incident light moves downward, and the light coming out from the other side moves upward.

So the candle gets shorter and moves downwards, and the image on the front light screen moves upwards.

If only the candle is adjusted, the candle should be adjusted upwards; Stool good.

If only the convex lens is adjusted, the convex lens should be adjusted downward;

If you only adjust the light screen, adjust the light screen up.

When the upper part of the lens is covered with a piece of paper, the original clear image will be darkened, but the image will still be complete.

Application of convex lenses.

The camera can be turned into an inverted, zoomed out real image.

The pattern on the slideshow forms a magnified, inverted image through a convex lens.

The magnifying silver coarse mirror is a convex lens, which can be used to create a magnified and upright virtual image.

Candles are flammable solids that melt into liquids when exposed to heat and are slippery and volatile. When a candle burns in the air, it creates a chemical reaction that produces carbon dioxide and water, and the carbon dioxide and water vapor diffuse into the air, so the candle becomes shorter after burning.

The products of candle combustion are carbon dioxide and water, and the burning phenomenon in the oxygen panstate gas cylinder is that the flame brightly emits white light, emitting heat, and water mist appears on the wall of the bottle.

The main raw material of candles is wax paraffin, which is easy to melt, less dense and insoluble in water, and easy to volatilize by heat. When heated, colorless and transparent, it has a paraffin smell, and when cold, it solidifies into a white solid with a slight special odor.

At the moment when the candle is blown out, a wisp of white smoke can be seen, and the wisp of white smoke can be lit with a lit match, which can rekindle the candle, so it can be proved that the white smoke is a solid tiny particle produced by the condensation of paraffin vapor.

The candle becomes shorter after burning because the candle burns to produce carbon dioxide and water, and a small amount of ash, carbon dioxide and water vapor are diffused into the air, so the candle becomes shorter after burning. When a candle burns, the products of combustion are carbon dioxide and water. The burning phenomenon in the rotten pure oxygen cylinder is that the flame is bright and emits white light, releasing heat, and there is a mist of water on the wall of the bottle.

Light the candle, cover a cold and dry beaker above the candle for 5 minutes, and then quickly invert the beaker, and find that the inner wall of the beaker is blurred and water droplets are formed, indicating that the candle burns to produce water.

1.Move the light screen up.

2.Adjust the candle position downwards.

Analysis: The direction of light propagation through the center of light remains unchanged, so that the object is above the main optical axis, and because the light passes through the optical center, the inverted real image is just below the main optical axis.

Pictured: If the candle becomes shorter, the light passing through the center of light rises and the light screen needs to be moved up.

If the image is downward, the candle flame moves downward, and if it is up, it falls in the middle of the light.

Summary. Hello dear! The candle behind the lit glass plate gradually becomes shorterThe observed phenomenon is that when the glass plate is moved, the flame of the candle becomes smaller and the height of the candle gradually becomes shorter.

Hello dear! The candle that is lit gradually becomes shorterThe candle behind the moving glass plate is observed that when the glass is moved, such as a bucket, the flame of the candle will become smaller, and the height of the candle will gradually become shorter.

Because when the glass pane is moved to the front or position of the candle, the pane will block some of the air, reducing the oxygen needed to burn the candle, so that the candle burns slower and the candle becomes shorter.