2 questions Suddenly scared to be quiet, why and People don t believe me, it breaks my heart 30

Maybe it's because your way of doing things is not very agreeable to everyone, you should communicate more with everyone. Let them know that you won't have such a thing, and you will be encouraged and happy!

Why refuse someone else's question? Since others asked, they said they cared about you. You always choose to reject others, how can others believe you? Isn't it?

Maybe you're under the pressure to the top, so you're scared.

As for your second question.

People are curious, and they like to talk and gossip.

I definitely like to ask questions about things I don't know or can't do.

When you get to know it, you'll say, oh, I see.

If you want them to believe in you, you have to let them know together. It's not like you can do what you want, just let them have a general understanding, and then slowly follow you... I won't fail to believe you.

Before. He also said what he used to do.

It's over.

Some things are not about finding answers to questions.

It's about getting real experience in searching.

Saying goes. There is no process, where comes the result.

Believe? It may be that you have done something in the past that has disappointed everyone in you.

But that's all before.

People are constantly changing.

Find your true self.

Previously they didn't believe you.

Still don't believe it.

Then do it well. Make them believe in you.

Say to yourself: Yes, you have to trust me.

Do too much, and everything will be fine.

Go your own way and let others say it.

Believe in yourself.

Okay, done.

First of all, confirm whether you are really working hard, reflect seriously, if you confirm that you ask others why they don't trust you, you can't make all the people in the world believe in you, and you are not afraid of anything if you have a clear conscience.

You really need to be quiet.

A person's life will not be smooth, you will not fall down only if you are getting stronger and stronger.

I don't understand what you mean.

The child is not big, and this bad problem must be reversed. You can pay equal attention to grace and power, so that he knows that he shouldn't be like this. Zhou's children know what to do and what not to do.

Why is the trunk round.

In the process of observing nature, I stumbled upon the shape of tree trunks that are almost round—empty cones. Why is the trunk conical? What are the benefits of a conical trunk? In order to explore these questions, I conducted more in-depth observation, analysis and research.

With the help of my tutor, I looked up the information and learned that the stem of the plant has the role of supporting the plant body, transporting water and other nutrients. The stems of trees are mainly made up of vascular bundles. Although the stems of woody plants will thicken year by year, the number of wood fibers of the stems is certain within a certain time range, that is, the cross-sectional area of the tree stems is certain.

Then, we designed an experiment around a certain cross-sectional area of the trunk, assuming that the cross-section of the trunk grows into different shapes, to explore the reasons and advantages of the conical shape of the trunk.

After experiments, we find that: (1) when the cross-sectional area and length are constant, the longitudinal support force of the triangular prism object is the largest, and the lateral bearing force is the smallest; The longitudinal support force of cylindrical objects is not as good as that of triangular prism objects, but the transverse bearing force is the largest; (2) Trunks of different shapes of equal mass, with short cone-shaped trunks bearing the greatest wind force; (3) Wind is a natural phenomenon that affects the shape of the cross-section of trees and the height of tree growth. The trunk is almost conical, with a low center of gravity, and with a large root system connected to the earth, the center of gravity is lowered lower and the stability is greater; (4) The trunk has a circular cross-section, which can reduce damage, has stronger mechanical strength, and can withstand the attack of wind.

At the same time, due to the influence of wind, the degree of bending of the trunk is similar, regardless of the direction from which the wind comes from, the resistance of the trunk is similar, and the trunk is not easily damaged.

The above experiments reflect the laws of nature and the enlightenment of nature: (1) a columnar object with a triangular cross-section has the largest longitudinal support force, and its form can be used in construction, such as angle steel; (2) The cross-section is a circular circular object, which has the greatest lateral bearing force, and similar forms of building materials can be seen everywhere, such as TV towers, telephone poles, etc.

In the process of observation, experimentation and analysis, I gradually explained and revealed the mystery of the cone-shaped trunk, increased my knowledge, and applied the knowledge I learned in connection with practice, which not only consolidated the knowledge I learned, but also improved my interest in learning, and I also learned the methods of scientific observation and analysis.

1.Small magnetic needles for color projection.

The magnetic needle is the compass. The compass is one of the four great inventions of our country. In current physics teaching, a small magnetic needle can be used to determine the direction of a magnetic field.

However, it is very inconvenient to use the magnetic needle that is the best in the market or the investigation of the superior department. When the teacher was doing the magnetic field direction demonstration experiment, the students could not see clearly below, so the teacher had to walk down with the instrument and show the students one by one, which was very time-consuming. What to do?

After the students tried their best to find a way, they finally made a simple color projection small magnetic needle, which can be used as a compass and can be projected on the projector, so that the whole class can see the direction of the magnetic field, which provides great convenience for teaching experiments. 、

Simple projection, small magnetic needle, simple structure, and ordinary materials. It is made of buckle steel pins, pins, plexiglass strips, and transparent projection film material. Here's how to make it:

Thread the two steel needles on the two steel needles respectively, and pay attention to the balance of the two steel needles. Then cut the transparencies into pointed long films, glue them to the steel needles with 502 glue, one end piece, pay attention to symmetry, and then paint them with red and green colors. In this way, the upper part of the magnetic needle is completed.

The plexiglass strip is sawn into a block, and then ground into a round shape as the base of the magnetic needle, which is scalded in the middle of the round plexiglass. Note that the pin should be perpendicular to the base. The recess of the small buckle is used as a rotating bearing support hole.

Place the bearing on the tip of the needle so that the magnetic needle rotates on the tip. The last piece is to magnetize the small magnetic needle by wiping the S pole of the bar magnet from the middle of the magnetic needle to the green side, which is the N pole. In this way, the small magnetic needle is magnetized.

By placing a small self-made magnetic needle on the projector, you can see the direction of each point of the magnetic field from the screen at a glance.

To make a periscope, you only need two small square mirrors of the same size and a piece of cardboard. If your small mirror is ten centimeters long and seven centimeters wide, then you should prepare a piece of cardboard with a width of 4 7 = 28 centimeters. The length of the cardboard can be decided for yourself according to the conditions.

The cardboard is longer, and the periscope can be made taller.

Three parallel lines were drawn on the cardboard, each with a distance of seven centimeters, as shown in the diagram. Cut off the blacked-out parts. Use a knife to make a mark along the dotted line (be careful not to cut through).

Then, fold it around the table to make a rectangular box and glue it with kraft paper.

Glue the small mirror with white tape as shown in the picture below (so that the angle between the small mirror and the long carton is equal to 45°). Two small mirrors are aligned in parallel. In this way, a periscope was made.

If the small mirror in your hand is less than 10 centimeters long, you can calculate the size of the carton according to the Pythagorean theorem, provided that the angle between the mirror and the carton is 45°. It's fun to use a periscope to ** the scenery outside the window, and you can also use it to hide and seek. Of course, periscopes were made primarily for scientific research and national defense.

Scientists use periscopes to observe the launch of rockets in the basement; When conducting atomic physics experiments, researchers use periscopes to observe dangerous experiments that are radioactive through a thick protective wall. When the submarine is underwater, it must also use a periscope to observe the situation on the sea surface.

Who invented the periscope is now impossible to find. The earliest ancient book in the world to record the principle of periscope is the Huainan Wanbi Technique in China in the second century BC. The book records such a passage: "Take a large mirror and hang it high, and put the water tray under it, and you will see the neighbors." ”

In ancient times, under the eaves of some ancient temples in the deep mountains of our country, a large bronze mirror is often hung obliquely, if a basin of water is placed on the ground within the temple gate, the mirror is aligned, this is made into a simplest periscope, and the sheep intestine path and passing pedestrians outside the temple gate will be reflected in the water. To make a periscope, you only need two small square mirrors of the same size and a piece of cardboard. If your small mirror is ten centimeters long and seven centimeters wide, then you should prepare a piece of cardboard with a width of 4 7 = 28 centimeters.

The length of the cardboard can be decided for yourself according to the conditions. The cardboard is longer, and the periscope can be made taller.

I don't want to write it! It's annoying! Why is science so annoying!

Do you need to write ** in elementary school now?

What you write yourself is the best, and it is useless to imitate others!!

Heheheheha