Ask a few questions about science

1 Ask a question:

What do you see when you observe the phenomenon of sunlight passing through the shade of trees? What questions can be asked?

See a lot of circular spots, where does this spot come from? I also saw some non-circular spots, how did these spots form? )

2 Make conjectures and **:

It may be that the hole that meets the light is approximately circular, so that the edge of the shadow is approximately circular, and if the aperture that transmits light is non-circular, then the light spot formed is also non-circular;

It may be that the sun is too far ahead to form a spot (image) The size of the hole may affect the shape of the spot.

Which conjecture is correct?

3. Gather factual evidence.

Students work in groups of 2-3 and observe the image of sunlight passing through small holes in the paper on the screen.

The image is made by letting sunlight pass through various small holes of different shapes (triangles, squares, diamonds, trapezoids, etc.) on the piece of paper.

The image is formed by letting sunlight look through various large holes of different shapes (triangles, squares, diamonds, trapezoids, etc.) on the paper.

4 Draw conclusions and explanations.

By analyzing the collected facts, it can be concluded that the image formed by the small hole is circular, independent of the shape of the hole, and when the hole is large to a certain extent, the circle disappears, and a spot similar to the shape of the hole is obtained.

The principle of direct advance of light can explain the above conclusion: that is, a luminous point on the surface of the sun forms a spot on the screen through a small hole, and all the luminous points form a spot corresponding to themselves, thus combining into an image of the sun.

1.The shadow of the sun digs.

2.Because light travels in a straight line

First, the Earth is a sphere. Assuming that it is excavated by hand and has unlimited physical strength, if you dig down, it is estimated that before you can dig the earth's fiber, it will be squeezed into a meatloaf by the strong pressure of the earth's interior, and it will be burned into ashes by the hot lava in the mantle. But if you have any cutting-edge technology that can overcome ultra-high temperatures and pressures, Qingbi will feel the gravity inversion when you dig through the core.

If you dig down on the surface (i.e., in the direction of your feet on the ground) and cause the direction of your gravity to change after passing through the core, (originally your feet are stepping on the ground), you must switch your head and feet in the direction of the crack, and it will feel like you are digging up (i.e., with your head on top of the earth), and when you dig to the surface, it will feel the same as before. However, it is estimated that your project to dig through the earth will lead to a series of disasters such as floods, tsunamis and volcanic eruptions, which may lead to the disintegration of the earth.

Personal opinion only, if there is any similarity, it is purely coincidental).

The air in the bottle is covered by the surface of the water.

It cannot be ruled out in time.

Therefore, an empty bottle is placed in water with the mouth facing down for a short time.

The water can't get in. Imagine that the bottle has a large mouth and becomes a mug, and the latter is well understood.

Air is easily exhausted from the outlet.

It's easy for water to flow in.

It's raining in the summer.

It will be noticeably muggy.

The temperature is high. Atmospheric circulation activity intensifies.

Low air pressure (high temperature) at the bottom and low air pressure at high altitude (clouds).

Winter is the opposite. Of course, the solubility of the gas is related to the pressure.

The solubility of the gas decreases as the pressure increases.