A geography question about time, how to calculate geographic time in this question

From the figure, 20° represents 20°W, 70° represents 70°E, 160° represents 160°E, that is to say, 70°E is located in the middle of 20°W and 160°E, because the relationship between the morning and dusk lines and the equator is bisected with each other, so the intersection of the meridian and the equator where 70°E is located is the intersection of the morning line and the equator, that is to say, 70°E is 6:00, (because the line given in the figure is the morning line). If you want to find Beijing time, you can only ask for 120°E local time, the difference between 70°E and 120°E is 50°, which is equivalent to 3 hours and 20 minutes, and 120°E is in the east of 70°E, according to the principle of east plus west minus, the Beijing time is 9:20

Upstairs there is a misunderstanding, and the morning line is the line segment in the diagram.

The morning and dusk circle divides the earth's various latitude coils into day arcs and night arcs, and judges the length of day and night by the arc length. But this question does not cover any of these.

The Circle of Dawn and Dusk is a great circle that passes through the center of the earth, and the ends of the morning lines are at a point on the meridian of 20° and 60°, respectively. Then, according to geometric knowledge, its intersection with the equator must be on the 70° meridian, that is, the 70° meridian is 6:

00.The representative meridian of Beijing time is 120°E.

Since the diagram shows the view of the earth from the outside of the earth, the direction is uncertain, and the meridian does not account for east or west longitude, so 70° may be 70°E or 70°W. So there should be two outcomes to this question.

Referring to the time zone map, the longitude difference is 15° and the time difference is one hour, and the east plus west is minus.

The results are as follows: If the 70° meridian in the figure is 70°E, the result is 9:20, and if the 70° meridian in the figure is 70°W, the result is 18:40

As can be seen from the diagram, this is the Eastern Hemisphere (20°W-160°E), the morning line intersects with 70°E (located in the East 5th Zone), and the point b is 6:00 am (that is, 6:00 in the zone between 60°E and 75°E in the East 5th Zone); Beijing is located at 116°E, which is the 8th East Zone, which is 3 hours ahead of the 5th East Zone, and the zone time should be 9 o'clock.

However, when every 15 degrees of longitude on the earth is a zone, which is equivalent to 15° for 60 minutes, 70°E is 5° worse than 75°E, that is, 20 minutes worse, so the accurate time in Beijing should be 9:20

Can't see clearly, meaning 70° is the morning line? For the question of time zone, the building mainly understands the longitude where the East Eighth District is located, as well as the knowledge of how many degrees of longitude is different and how much time is different.

Answer: Beijing time is 8 a.m.

Problem solving ideas: At first glance, it seems that the conditions of this problem are insufficient and unsolvable, but there is still a solution. The main point of the solution is the sentence "Only the dots in the picture are July 7". There are two points of information in this:

1. A o b The three locations are on the same date.

2. Only the date of each point on the half of the earth facing us is July 7, and any place on the half of the earth on the other side is a different date.

Since there is an international date line on Earth, the line is located on the 180th degree longitude in the Pacific Ocean, and the dates on both sides of it are different. If the two points A and B, which are 180 degrees apart, are on the same date, and the half of the world on the opposite side are all on the other date, then there is only one case: A is at the prime meridian of the 0 degree meridian, B is at the International Date Line of the 180 degree meridian, and B is at noon and A is at zero hour, that is, A's clock shows 0 o'clock, and B's time is 12 noon.

In this only case, the time in Beijing, which is in the East 8th District, is 8 a.m. Finish.

The figure shows that there are now 180 degrees of longitude on July 7, and there are only two date lines, the 180° meridian is one, and the other is the meridian where 0 o'clock is located, which means that the meridian where 0 o'clock is now 0°, since the 0 ° meridian is 0 o'clock, it is not difficult to calculate that Beijing time is 8 o'clock.

1 South-East

2 7:54 a.m. local time on 22 December 8:00 a.m. local time.

Daylight The day of the winter solstice, the polar day within the Antarctic Circle

3 December 22, 13:54 Direct shot's 'w .

4 The days are long and the nights are short.

1. When the local time of Jinan (117 °E) is 12 o'clock, and the local time of Chengdu is 11:08, the longitude of Chengdu is (

2. An airplane flew from Shanghai (East 8th District) to San Francisco (West 8th District) in the United States at 17 o'clock on October 1st, and it took 14 hours to fly. When you arrive at your destination, the local time is (

15 o'clock on the 2nd of the month.

3 o'clock on the 2nd of the month.

15 o'clock on the 1st of the month.

3 o'clock on the 1st of the month.

3. At 22:30 on December 3, 2002, Beijing time, the World Bureau of Expositions announced in Monaco (East Zone 1) that Shanghai had won the right to host the 2010 World Expo

At 15:30.

Day 9:30 c

9:30 on the 3rd.

At 15:30.

4. When the international standard time is noon, the city with a district time of 20 o'clock is (a.).Sydney (around 150°E).

b.North Rusui Jianjing (near 120°E).

c.Los Angeles (around 120°W).

d.Accra (near the 0° meridian).

The local time at point A is 16 o'clock, the equatorial region rises at 6 o'clock and sets at 18 o'clock throughout the year, the morning and dusk morning draft line in the map is the dusk line, and the intersection of the dusk line and the equator is 18 o'clock when the meridian is located, and the meridian line where A is located is 30 degrees different from the meridian at 18 o'clock (that is, two hours of bright filial piety), just take the meridian line where A is located in the above picture A is west of the meridian at 18 o'clock, and the time decreases to the west, is it clear? Hope.

The meaning of this question is that when the whole world is the same day, Beijing time, that is, the place of 120° east longitude, there are two boundaries of the earth's date, one is the international date line of 180 ° longitude, and the other is the meridian where zero time is located.

When the whole world is on the same day, the two lines should coincide, i.e. the 180° meridian is 0:00 at 24:00.

Do you understand that the place at 120°E is 20:00?

If it's October 1 in the world, the international date line is exactly 0:00, so that the world will have the same date.

In this way, Beijing is the East 8th District, and the international date change line is 0 o'clock, so Beijing is 8 o'clock.

At this time, the earliest place is 24 o'clock on October 1, and the latest place is 0:00 on October 1, that is, 24 o'clock in the East 12th District, 0 o'clock in the West 12th District, and Beijing is in the East 8th District, so it is 20 o'clock (4 hours later than the East 12th District).

The West 12th Zone on the east side of the International Date Line is the latest time zone in global time. When the whole world is on October 1, the West 12th District will be at 0:00 on October 1, and the East 12th District will be at 24:00 on October 1, so the East 8th District, where Beijing is located, will be at 8 p.m. at this time.

In other words, the world-time boundary is zero or 24 o'clock.

So you know the time of the radius, and then you can calculate the diameter of Beijing, 18:30

If all the dates in the world are October 1, then the 180-degree meridian coincides with the meridian at 0 o'clock, so the East 8th District, where Beijing is located, is 20 o'clock on October 1.

At 20 o'clock, Beijing is in the 8th district of the east.

The same day in the world, i.e. the international date change line, is 24 o'clock or 0 o'clock.

West longitude 150 is the West 10 district.

Shanghai is the 8th zone in the east, so the difference between the two places is 18 hours, if the same time zone is counted, the 15 days should be 8 o'clock on March 20, but the time zone is different and sailing from west to east, so 18 hours should be subtracted, so it is 14 o'clock on March 19.

The information given in the title is very subtle, but what should be given is given: r means that this picture is a side view of the earth at 180°, as we usually do, but there are no other meridians; Only the points in the picture are July 7, indicating three information, this time is summer (this can also be known from the aphelion point), and there is a point A is 0, then point B is 12 o'clock (this teacher should always emphasize); The third is the semicircle with point b as the core is the international date line. So the idea comes out:

The longitude of point b is 180°E, and the time is 12 o'clock, then Beijing time is: 12-(180-120) 15=8, and the answer comes out, Beijing time is 8 o'clock in the morning.

The aphelion point is around 8 o'clock in July!