How to calculate the resultant force of balance force
If it is not vertical, the following method can be used:
the angle between F1 and F2 is θ ， If the resultant force is f,
is used as the auxiliary line as shown in the figure, then F1 & # 39= F1cos θ 、 F1" = F1sin θ
from mathematical knowledge:
f ^ 2 = (F2 + F1 & # 39;)^ 2+F1"^ 2=(F2+F1cos θ)^ 2+(F1sin θ)^ 2=F2^2+2F2F1cos θ+( F1cos θ)^ 2+(F1sin θ)^ 2=F2^2+2F2F1cos θ+( F1cos θ)^ 2+(F1sin θ)^ 2=F2^2+2F2F1cos θ+ F1 ^ 2
therefore, the size of resultant force is:
F = √ (F2 ^ 2 + F1 ^ 2 + 2f2f1cos) θ)
extended data:
principle and application of resultant force:
the direction of force F is the direction after the combination of several forces
Force is a vector, and resultant force refers to the vector sum of multiple forces acting on the same object. The resultant force is a vector, and the addition and subtraction of vectors satisfy the parallelogram rule and triangle rule If the two forces are not collinear, the direction of diagonal is the direction of resultant forceif the directions of the two forces are the same, then the resultant force is equal to the sum of the two forces and the direction remains unchanged
if the directions of the two forces are opposite, the resultant force is equal to the difference between the two forces, and the direction is the same as that of the larger force
If two forces are equal forces, the resultant force is zero. ∑F=0
walk to beigongmen station of Summer Palace and take special 10, get off at Xiyuan Hospital Station and take bus 664, and walk to block a of Wanliu Yicheng center at the south entrance of Wanliu middle road
Peking Opera, in our eyes, is the "quintessence of Chinese culture". It has its own set of skills: singing, reciting, sitting and fighting. The four skills that need long-term training come together, that is, the way to make a fortune in Peking Opera, plus the colorful facial makeup, whether it is blue face, yellow face or white face. With a little ingenuity, it can represent the great right and wrong of good and evil, loyalty and treachery, It is worthy of being called "national quintessence"
in the history of Peking Opera in China, the most famous Peking Opera master is Mei Lanfang, who founded the "Mei school"
Although Mei Lanfang worked in the "lower class" at that time, he never lacked Chinese spirit. In that era of war, he did not choose to live a life full of money. Instead, he donated his own money when the country was in danger. This rare patriotic feeling is worth learning for every Chinese, What we need to admire is not only Mei Lanfang's superb opera art, but also his patriotismregister one by yourself. It's very fast
Introction to tribal conflict
the construction of tribes in the game is a transitional period from one to six. Don't stay too long. It's better to upgrade all the buildings in the tribe after the completion of the construction, and quickly upgrade seven books, because the defense below seven books is relatively low; The level of defense facilities is not high either). Seven books is the beginning
the construction and upgrading of buildings have priority. This is an advanced vegetable stealing game (which is generally recognized). When you are considering upgrading buildings, you should give priority to increasing your fighting capacity, that is, your vegetable stealing game. It is not enough to build money and holy water by yourself in the early stage, so you need to rob other tribes to ensure the development of your own tribe. Personally, I think we should consider upgrading the experimental test, magic factory, barracks, training camp, tribal castle and other buildings to improve our offensive ability. Of course, in order to fight tribal war in the later stage, we can upgrade the offensive buildings to a certain extent, and then upgrade the defense facilities according to the length of time to increase our tribal defense ability
about tribal farmers, farmers are very important in this game. There are at most five farmers in each tribe, so I think this game is very balanced. Every farmer needs gems at different prices. The first one is his own. The second one needs 250 gems, the third one needs 500 gems, the fourth one needs 1000 gems, and the fifth one needs 2000 gems. Therefore, gems should not be wasted in this game, because if you use gems to build soldiers, it is not worth upgrading buildings, It will take a few days or even longer to upgrade a building in the later stage. It's a bit unfair to spend the precious stones. Of course, local tyrants can be another matter. If they don't spend any precious stones, a third farmer can come out in four books
the first method is to buy 500 gems for 30 yuan in the game store. The second method is to remove obstacles and get gems at random (there will be a treasure box from time to time). The third method is to do tasks. A key task is to reward 450 gems when you get 1250 cups, This is also a way to get a third farmer
about traps, in fact, traps are very useful. Many players think that these traps exist like chicken ribs. In fact, this idea is wrong. At present, many guiding formations are popular in the game to prevent fat people and wild boars. In fact, the effect is very good. When fat people and wild boars enter the formation, you will find that fat people and wild boars are flying all over the sky. So traps should not be placed randomly. For example, aerial bombs and air search mines can be placed close to the empty rocket or the air arrow tower. Generally, your prevention and control facilities will pass through this place if people want to hit you; Stealth bombs don't work very well for fat men and other bloodthirsty arms, but for barbarians, archers, goblin and other bloodthirsty arms, one blow can kill one; Invisible spring is the only way for fat people and wild boars to walk, which makes it difficult for them to walk. The layout of the trap is mainly for your own formation. Observe how the enemy attacks your tribe, and then modify it
in fact, there is not much to say about resources grabbing. There are many methods available on the Internet. In the early stage, I recommend the low-cost diaosi Liu (that is, yellow hair with Archer or goblin, as well as the bomber), which can be played once every ten minutes, which is very convenient. However, we should pay attention to the flexible use of methods. We should pay attention to the proportion of arms and the level of arms. We should not keep the same. We should use one method to death
as for the formation, there is no invincible formation. A good formation is targeted, such as the defensive object, fat boar, etc. you can take the method of guidance to guide them to the trap, or use the power tower to divert them, etc., but there is no perfect formation. The formation needs to be adjusted and modified constantly, and you can learn from other people's tribes. Also, whether your tribe wants to protect resources or protect the cup is also very important
a lot of people will put Big Ben outside to cheat the shield, which is also a good way
if it is to protect resources, we should also pay attention to adjusting the location of resources. For example, if there is less money and more water, we should transfer the water to the inside and put the money out. These are details that need to be summed up slowly by ourselves
in fact, there are some small skills to protect resources, such as water conservation. After the barracks are full, you can build more high-end soldiers in the training camp, because the soldiers being built in the training camp will be returned 100% of the resources after cancellation. As for the security deposit, there is no good way. Some people say that it is not cost-effective to buy a national flag every 10W, but only one tenth of it will be returned when you sell it, Personally, I prefer to brush the wall with the extra money, so I'm not afraid of being robbed by others
there are many things that you can communicate with players in the tribe when you join the tribe
as for tribal warfare, it will not affect resources, trophies and shields. How to fight a good tribal war, we need to pay attention to several aspects, here is mainly for the novice, the old bird knows
the first thing to note is that when many novices fight tribal wars, they don't even lead out the castle soldiers to destroy them, so they throw all the soldiers down. As a result, all the soldiers are easily destroyed by the enemy castle soldiers, and even the little waves don't turn up. Every time, they lose the tribal wars, which makes people speechless. In fact, the method of leading soldiers is very simple. You can lay down a small soldier close to the enemy castle, then slowly lead them out of the attack range of the arrow tower, and finally eliminate them. It's better to bring lightning potion as a tonic. The method of leading the king is the same. I won't repeat it here. This method is written as a reference for novices
the second thing to pay attention to is the enemy's trap. If the trap is built-in, there will be many spaces in the array, which are not so compact. These spaces are the places to pay attention to. They are most likely to set traps to avoid being cheated; The method of external defense of traps is not to release soldiers all at once. You can first release one or two soldiers to explore the way, and then release them. It's better to keep some soldiers to prevent accidents
the third thing we should pay attention to is that fighting tribal warfare is not fighting resources. We should be well prepared. First, we should investigate the targets we want to attack, and then we should make targeted attack strategies. We should take the potion with us, and the arms with us will be full. Don't even hit a star because of improper preparation. The main purpose of tribal warfare is to fight stars. It's better to find enemies who are sure to fight three stars. Only in this way can they make a good contribution to the success of tribal warfare. After all, everyone has only two chances. If they lose by a small difference, it's too tragic
many specific attack strategies will not be mentioned, because each attack strategy needs to be understood and used flexibly. Only when you try and summarize your own resources, can you find a good attack method.
In the spring and Autumn period, King Jing of the Zhou Dynasty made large coins with flat shoulders and empty heads. But before that, there were two kinds of copper coins, light (Zi) and heavy (MU), which were circulated at the same time. These two currencies of different weights may be yuan money. Although the yuan coins found in the literature have not been unearthed, it can not be said that there are no such coins. Just as there are 12 kings in the Western Zhou Dynasty, and no royal mausoleum has been found so far, it can not be said that there are no royal Mausoleums in the Western Zhou Dynasty. After King Jing of Zhou Dynasty, the dishonored cloth and yuan money circulated in parallel in the area controlled by the royal family of Zhou Dynasty. The granary of the Warring States period was found to the east of qujiatun in the south of Luoyang Wangcheng site. 116 coins were unearthed from the granary No. 62. There were not only dishonoured cloth such as "Wang", "Dongzhou" and "anzang", but also 47 round round hole coins. Among them, there were coins written in the form of "anzang". It was believed that the coins of Zhao Dynasty flowed into the Wangcheng, and the others were mostly cast by the Wangji of the Eastern Zhou Dynasty, It can be seen that its dishonoured cloth and round money were also the currency circulating in the Eastern Zhou Dynasty ring the spring and Autumn period and the Warring States period. In the middle and late Warring States period, the Zhou royal family split into two principalities, the Western Zhou and the Eastern Zhou, casting two kinds of money in their tiny areas. Its round hole still abides by the ancestral system
there are several ways to describe the image of Yuanqian, and the reason is that the image of Yuanqian is based on jade. In the Western Zhou Dynasty, the system of "food officials for Instry and commerce" was carried out. Instry and commerce were managed by the government and served the slave owners and nobles. Because the nobles liked to use foreign ornaments, seashells, Bi rings and so on were used as the general equivalents of commodities earlier, and then became the image of coins. As Wang Xiantang said: "the ring of jewelry has been used as wealth by merchants. According to the inscriptions on gold and the book of history, the Zhou Dynasty changed the casting of copper from ornaments to trading. According to the textual research of the coin, the ring coin was already named ring when it was used as a famous ornament. When it was made into currency, it was also named ring. The same name, the same form, the same order. " As for the word "Yuan" of "half round" money, Guo Moruo said: "Yu is called" Yuan ", which is the beginning of the jade ring, like a ring in the chest of a garment.". China has a fashion of worshiping jade since ancient times. Ancient noble women wear jade rings. The book of rites says: "walking makes the sound of wearing jade rings." It was also used as a gift for court engagement, sacrifice, funeral and marriage. It was an expensive commodity in the market at that time, and had the conditions to become a general equivalent. In the stage of physical currency, Zhuyu was the "Shang coin". According to Erya Shiqi, in jade, the one with big side and small hole is called Bi, the one with big side and small hole is called yuan, and the one with equal side and hole is called ring. Bi, yuan and Huan are similar and can be used flexibly. The round coin is round with a hole in the center, which is consistent with the shape of Bi, yuan and Huan
the round round hole round coin in the state of Qin adopted the form of Zhou round coin, and still maintained the image of Bi, yuan and Huan: the round character was written in the form of Jin script, and before Shang Yang's reform, the state of Qin still used the big seal script of Zhen script, which Wang Guowei called "western local script", which was different from the later small seal script. It can be concluded from the shape and text that the round hole was the early form of Qin coins before the round square hole, and the coins of Xiangong and Xiaogong were round hole coins