Why is the sun at an altitude angle of 45 degrees at noon when the shadow of the south wall obscures

<> condition is missing the distance between the two walls.

Hello! Your topic is incomplete. The original question should be:

A book is only for the wall, so why not let him be three feet. The Great Wall is still there today, and Qin Shi Huang is not seen. The "Six Feet Lane" in Tongcheng City, Anhui Province (30°N, 117°E) is a testimony to the Chinese nation's virtue of modesty and courtesy.

The alley runs east-west, 6 feet wide, with a wall 8 feet high, with stone at the bottom and cobblestone on the floor. Complete 1 2 questions accordingly.

1.When the noonday shadow of the south wall is just 1 4 of the area of the north wall, the coordinates of the direct sun point are.

a.(15°n,20°e) b.(15°n,117°e) c.(15°s,1°e) d.(45°n,120°e)

Choose C for this question. At 12 o'clock in the local area, the meridian of the direct sun point is 117 °E, and when the noon shadow of the south wall just covers 1 4 of the area of the north wall, the shadow length of the south wall should be 6 + 8 1 4 = 8 feet. The shadow length of the south wall is as high as the height of the wall.

Therefore, at this time, the altitude angle of the sun at noon is just equal to 45°, so the difference between the latitude of the direct point of the sun and the local latitude is 45°, so the latitude of the direct point of the sun is 15°s, so the direct point of the sun at this time is (15°s, 117°E).

Whether it is noon in a certain place or not has nothing to do with the specific value of the sun's altitude angle.

For areas north of the Tropic of Cancer, to see if it's midday somewhere, just meet one of two conditions.

One is that the sun is located geographically due south of a certain place; The second is when the solar altitude angle is the maximum value of the day.

This is because, in the case of local time in a certain place, the noon hour of the day must be in the middle of the time from sunrise to sunset, and at this time, the sun must be located due south of the geographical area of the place, and at the same time the time when the solar altitude angle is at its greatest.

As for the specific value of the solar altitude angle, the maximum value of the solar altitude angle is different every day because it is related to the latitude of the place and the season at that time.

When the solar altitude angle is 45°, it is an isosceles right triangle if imagined on flat ground.

In general, the larger the height angle of the sun at noon, the smaller the area that hits the room, that is, the irradiated area is small in summer and large in winter. In areas north of the Tropic of Capricorn, the sun's rays enter through the south window at noon; In areas south of the Tropic of Capricorn, the sun's rays enter through the north window at noon; The area between the Tropic of Cancer may be shot in from both the south and north windows at noon.

No matter what time it is, if the height is equal to the shadow length, the sun altitude angle.

It must be equal to 45 degrees.

This is an equilateral right triangle.

The three sides are the height and shadow length are right-angled edges, and the line between the top of the head and the top of the shadow is hypotenuse.

The apex angle of this triangle is a right angle, 90 degrees; The angles of the other two corners are equal, both 45 degrees.

The two right-angled sides of an equilateral right-angled triangle are equal in length. Since the two right-angled sides are height and shadow length respectively, when Feng Ran's height is equal to the shadow length, the angle of these two angles must be 45 degrees.

Illustrate with bamboo poles and pole Qiaoji.

Why does the solar elevation angle change at noon? Because the sun must be on the Tropic of Cancer at the moment of the summer solstice, at this moment, the sun can begin to move gradually to the south, until the moment of the winter solstice, the sun can move to the Tropic of Capricorn, at the same time, the sun can begin to move gradually to the north, that is to say, the sun is constantly moving every moment of the day, not only from east to west, but also from the winter solstice from the south to the north step by step, from the summer solstice the sun from the north to the south step by step, therefore, Theoretically, we can't be the same angle of the sun at noon every day, from the ordinary practice, the angle of the first day and the second day, it is not easy for us to find, if you look at the value of the noon sun altitude angle after a month, it is easier to find.

The sun rises in the east and sets in the west, and the rotation and revolution of the earth causes the sun to be in different positions.

The general law of the change in the height of the sun at noon:

The decrease from the latitude of the direct sun (in this case, 90°) to the north and south is equal to the difference between the local geographical latitude and the latitude of the direct point (the difference between the southern latitude and the northern latitude is the sum of their values).

Since the direct point of the sun moves between the Tropic of Cancer, so:

1. In the area between the Tropic of Capricorn, there are two opportunities for direct sunlight a year, and the height of the sun at noon is the maximum, at 90°. A minimum occurs when the Sun shines directly on the Tropic of Capricorn. Except for the two minima, which are the lowest at the equator, the other regions are the smallest when the sun directly hits the Tropic of Cancer in the other hemisphere.

2. In the area outside the Tropic of Cancer, the Tropic of Cancer can be included, which is the largest when the sun directly hits the Tropic of Cancer in the home hemisphere and the smallest when it directly hits the Tropic of Cancer in the other hemisphere.

For example, Beijing is about 40 degrees north latitude, and during the summer solstice in the northern hemisphere, the sun shines directly on the Tropic of Capricorn, and the noon sun height here is the largest, about; On the winter solstice, the sun shines directly on the Tropic of Capricorn, and the height of the midday sun here is the smallest, about.

Because of the rotation of the earth, the direct point of the sun on the earth reciprocates between the Tropic of Cancer once a year. Take the area through the Tropic of Cancer in the Northern Hemisphere as an example: when the sunlight directly hits the Tropic of Cancer in a year, it is the summer solstice solar term in northern China, and the sun is directly above the head at noon, that is, the solar altitude angle is 90°, which is the maximum value of the year; When the sunlight hits the Tropic of Capricorn directly, it is the winter solstice solar term in the north of China, and the solar altitude angle at this time is the minimum value of the year.

In short, it is the change in the altitude angle of the sun and the division of the four seasons due to the revolution of the earth!

Yellow red angle.

The direct point of the sun moves between the Tropic of Cancer in a one-year cycle. On the summer solstice, the sun shines directly on the Tropic of Cancer (northern latitude), with the noon solar height north of the Tropic of Cancer reaching its maximum and the noon solar height south of the Tropic of Cancer reaching its minimum. On the winter solstice, the sun shines directly on the Tropic of Capricorn (southern latitude), and the situation is opposite to that of the summer solstice.

The rest of the time is a transition between these two states.

The existence of the yellow and red horns! Because the solar altitude angle is the greatest at noon every day. The yellow-red angle makes the direct sun point move south, changing with the change of the season, and what is said upstairs is referring to the difference in the direct sun point, the noon sun height of the direct sun point is the largest, but after all, there is only one place!

High midday is the time of day when the sun is at its highest.

This highest altitude varies with the seasons. It is lowest at the winter solstice, when the midday sun shines through the windows facing south into most of the rooms, and only a little on the windowsill during the summer solstice.

This maximum height also depends on the latitude you are in. If you are on the Tropic of Capricorn, north latitude, the sun is overhead at noon on the summer solstice, and its altitude is 90 degrees; Further north, as latitude increases, the height of the Sun decreases at noon.

Why is the noon gate so named? It is because the sun appears due south at noon every day, so the south gate of the palace is called the noon gate. Why does the sun appear due south at noon every day?

Hello! This question is still calculable. According to the formula of the noon solar altitude angle, 45°=90°-(34° direct latitude), so the direct latitude is 11°.

According to the same subtraction and difference, it can be known that the direct point of light may be 11° north latitude or 11° south latitude.

90-45=45 means that the latitude of the direct point is 45 degrees different from the known point, and then the latitude of the known point is 34°n, so the latitude of the direct point is 11°s

What degrees north latitude is the direct point of the sun?

The direct point of the sun can be found between the Tropic of Cancer.

There's a problem with your topic, I don't know what latitude he's in.

Yes, it is related to your region, and it is also related to the date and time, generally speaking, as long as it is within 68 degrees and 26 minutes, it is possible to reach the solar altitude angle of 45 degrees in a year, the first thing to be clear is that the maximum solar altitude angle of the day is 12 noon, which is what we usually call the noon solar altitude angle, so as long as your maximum noon solar altitude angle of the year is smaller than 45 degrees, then you will never have a day when the sun is sandwiched between 45 degrees and the ground (unless one day the earth is hit and the yellow and red angle is bigger.) = =

When the latitude is higher than 68 degrees 26 minutes, the solar altitude angle cannot reach 45 degrees even at noon on the second solstice, so it can be concluded that as long as you are between 68 degrees 26 minutes north and south latitude, you can have a solar altitude angle of 45 degrees......

Our country is as far north as 53n, and it is possible to reach 45 degrees ...... any one placeAs for the time, it will have to be analyzed on a specific date and in a specific place.

It's about 9 a.m., which is supposed to change depending on the season. You can use the pole to see the shadow method combined with trigonometric measurements, when the length of the shadow is the same as the real length of the object, this solar altitude angle is 45

Generally speaking, as long as it is within 68 degrees and 26 minutes, it is possible to reach an altitude angle of 45 degrees in a year.

Calculation formula (compared to any latitude): the absolute value of A h-B h = (A latitude - B latitude).