Know how pressure counts as friction
Publish: 2021-05-09 06:10:29
1. You can't withdraw money, can you? help
2. The calculation method of sliding friction is different from that of static friction. When solving the friction, we must distinguish static friction from sliding friction.
I. calculation of sliding friction
1= μ FN calculation.
(1) according to the force condition of the object, calculate the positive pressure FN.
(2) according to the formula F= μ 2. Two force balance method: the object is in the state of equilibrium (uniform velocity, static positive), according to the two force balance conditions to solve; 2、 Calculation of static friction force
1. Balance condition method is used to solve static friction force. As shown in Fig. 3-3-19, a static object is placed on the horizontal plane. When a person pushes the object with horizontal thrust, the object is still. According to the two force balance condition, the static friction force is equal to the thrust force,
2, The value range of static friction is O & lt; F ≤ Fmax is independent of the positive pressure between objects, so the formula F cannot be used= μ FN solution.
3. Maximum static friction Fmax The value is equal to the external force along the contact surface when the object is just sliding, which is the maximum value of static friction and greater than sliding friction. Generally speaking, they are equal, and the maximum static friction is Fmax.. The formula is Fmax= μ Static FN, μ Static is the static friction coefficient and specific dynamic friction coefficient between objects μ Slightly larger
I. calculation of sliding friction
1= μ FN calculation.
(1) according to the force condition of the object, calculate the positive pressure FN.
(2) according to the formula F= μ 2. Two force balance method: the object is in the state of equilibrium (uniform velocity, static positive), according to the two force balance conditions to solve; 2、 Calculation of static friction force
1. Balance condition method is used to solve static friction force. As shown in Fig. 3-3-19, a static object is placed on the horizontal plane. When a person pushes the object with horizontal thrust, the object is still. According to the two force balance condition, the static friction force is equal to the thrust force,
2, The value range of static friction is O & lt; F ≤ Fmax is independent of the positive pressure between objects, so the formula F cannot be used= μ FN solution.
3. Maximum static friction Fmax The value is equal to the external force along the contact surface when the object is just sliding, which is the maximum value of static friction and greater than sliding friction. Generally speaking, they are equal, and the maximum static friction is Fmax.. The formula is Fmax= μ Static FN, μ Static is the static friction coefficient and specific dynamic friction coefficient between objects μ Slightly larger
3. If we know the pressure between two contact surfaces, we don't need to consider gravity. Gravity is often confusing. The direct contact surface pressure is multiplied by the friction coefficient.
4. Let's take a look at the configuration of IP address of common network card, The content of the file is as follows: < br /
< br /
< br / < br / < br / < br /
< br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br /
the content of the file is as follows: < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br /
ipadr = 192.168.168.168.168.1.1.103, this is the static IP address you set, which is the static IP address you set you set as the static IP address < br / < br /
netmask = 255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.0 35guidance Or whether to activate the device when starting the network card service
the double network card binding service of bond under rhel6
the operation steps and precautions are as follows:
1. Precautions:
first confirm which two network ports are bound to avoid binding wrong network ports
2. Description:
here we take the two network ports binding eth0 and eth1 as examples
the configuration files are all in the / etc / sysconfig / network scripts / directory
operation steps
before binding, you need to shut down the networlmanger service completely, otherwise it will conflict with the bond network card
12 chkconfig networlmanger off # stop starting the service
service networlmanger stop # stop the network card management service, where the nm in the network card configuration file_ Controlled = yes / / whether the device eth0 can be hosted by the network manager graphic management tool. You can delete this line directly
1. Edit the new ifcfg-bond0 file
CD / etc / sysconfig / network scripts /
CP – rfifcfg-eth0ifcfg-bond0 # ifcfg-eth0 to ifcfg-bond0
LS # view the file, You can see the ifcfg-bond0 file
Add or modify the following contents:
# VI ifcfg-bond0
device = bond0
IPADDR = 192.168.1.155
netmask = 255.255.255.0
gateway = 192.168.1.254 # this IP information is customer request information
onboot = yes
bootproto = static
userctl = no
bonding_ Opts = "mode = 0 mimon = 100 primary = eth0" # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #. Don't delete or mask
userctl = no
onboot = yes
Master = bond0
slave = yes
bootproto = none
? Ifcfg-eth1
hwaddr = AB: CD: EF: 12:34:57. Note that the MAC address of eth1 should be reserved. Don't delete or shield
device = eth1
User = no
onboot = yes
Master = bond0
slave = yes
bootproto = none
note: if other network interfaces are not required to be set, all of them in the network card configuration file should be shielded or removed, and the MAC address must be reserved. In order to avoid the hard disk network card binding, resulting in network card sequence drift
but don't worry. In Linux system, there is a table recording the corresponding relationship between eth device network card name and MAC address
3. Modify the / etc / modprobe.d/dist.conf file, Add the following content:
alias bond0 bonding
Options bond0 mimon = 100 mode = 0 ﹥ the specific requirements of the construction site shall prevail
note:
mimon is used for link monitoring. For example, if miimon = 100, the system will monitor the link connection status every 100ms, and if one line fails, it will switch to another line
the value of mode indicates the working mode. There are four modes: 0, 1, 2 and 3, and the commonly used modes are 0 and 1. It should be selected according to the working mode provided by the switch
mode = 0 means that load balancing (round robin) is the load balancing mode, and both network cards work
mode = 1 indicates that fault tolerance (active backup) provides rendancy function, and the working mode is active standby mode, that is to say, only one network card works by default, and the other one does backup< Note:
A. bonding can only provide link monitoring, that is, whether the link from the host to the switch is connected. If only the external link of the switch is down and the switch itself is not faulty, then bonding will consider that the link is OK and continue to use it
B. the setting mode should be consistent with the switch setting mode
4. Restart the system
when the system starts up, it will automatically load the bond mole and activate the rendant network card settings. You can use the following command to judge:
? Ifconfig
you can see the information of bond0, and bond0 will automatically obtain the MAC address of eth0
if you confirm that the bond0 network card has been activated, you can test the switch by plugging in and out the network cable or ifdownethx operation. In the process of switching, the network connection is normal
careful people will find that the MAC addresses of the three network cards in bond0, eth0 and eth1 are the same.
< br /
< br / < br / < br / < br /
< br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br /
the content of the file is as follows: < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br / < br /
ipadr = 192.168.168.168.168.1.1.103, this is the static IP address you set, which is the static IP address you set you set as the static IP address < br / < br /
netmask = 255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.255.0 35guidance Or whether to activate the device when starting the network card service
the double network card binding service of bond under rhel6
the operation steps and precautions are as follows:
1. Precautions:
first confirm which two network ports are bound to avoid binding wrong network ports
2. Description:
here we take the two network ports binding eth0 and eth1 as examples
the configuration files are all in the / etc / sysconfig / network scripts / directory
operation steps
before binding, you need to shut down the networlmanger service completely, otherwise it will conflict with the bond network card
12 chkconfig networlmanger off # stop starting the service
service networlmanger stop # stop the network card management service, where the nm in the network card configuration file_ Controlled = yes / / whether the device eth0 can be hosted by the network manager graphic management tool. You can delete this line directly
1. Edit the new ifcfg-bond0 file
CD / etc / sysconfig / network scripts /
CP – rfifcfg-eth0ifcfg-bond0 # ifcfg-eth0 to ifcfg-bond0
LS # view the file, You can see the ifcfg-bond0 file
Add or modify the following contents:
# VI ifcfg-bond0
device = bond0
IPADDR = 192.168.1.155
netmask = 255.255.255.0
gateway = 192.168.1.254 # this IP information is customer request information
onboot = yes
bootproto = static
userctl = no
bonding_ Opts = "mode = 0 mimon = 100 primary = eth0" # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #. Don't delete or mask
userctl = no
onboot = yes
Master = bond0
slave = yes
bootproto = none
? Ifcfg-eth1
hwaddr = AB: CD: EF: 12:34:57. Note that the MAC address of eth1 should be reserved. Don't delete or shield
device = eth1
User = no
onboot = yes
Master = bond0
slave = yes
bootproto = none
note: if other network interfaces are not required to be set, all of them in the network card configuration file should be shielded or removed, and the MAC address must be reserved. In order to avoid the hard disk network card binding, resulting in network card sequence drift
but don't worry. In Linux system, there is a table recording the corresponding relationship between eth device network card name and MAC address
3. Modify the / etc / modprobe.d/dist.conf file, Add the following content:
alias bond0 bonding
Options bond0 mimon = 100 mode = 0 ﹥ the specific requirements of the construction site shall prevail
note:
mimon is used for link monitoring. For example, if miimon = 100, the system will monitor the link connection status every 100ms, and if one line fails, it will switch to another line
the value of mode indicates the working mode. There are four modes: 0, 1, 2 and 3, and the commonly used modes are 0 and 1. It should be selected according to the working mode provided by the switch
mode = 0 means that load balancing (round robin) is the load balancing mode, and both network cards work
mode = 1 indicates that fault tolerance (active backup) provides rendancy function, and the working mode is active standby mode, that is to say, only one network card works by default, and the other one does backup< Note:
A. bonding can only provide link monitoring, that is, whether the link from the host to the switch is connected. If only the external link of the switch is down and the switch itself is not faulty, then bonding will consider that the link is OK and continue to use it
B. the setting mode should be consistent with the switch setting mode
4. Restart the system
when the system starts up, it will automatically load the bond mole and activate the rendant network card settings. You can use the following command to judge:
? Ifconfig
you can see the information of bond0, and bond0 will automatically obtain the MAC address of eth0
if you confirm that the bond0 network card has been activated, you can test the switch by plugging in and out the network cable or ifdownethx operation. In the process of switching, the network connection is normal
careful people will find that the MAC addresses of the three network cards in bond0, eth0 and eth1 are the same.
5. Skills ~ practice more, the appearance time of each mine is regular, mostly in the remote corner ~
official website, there are mines, distribution map ~
Level 1 mining runs in tianshengyuan, mining when you see a mine, you don't see what you go to mining
the iron ore of grade 1 is only 10 silver, and benzene is dying<
to level 2, it's time to upgrade while fighting monsters. Don't deliberately go mining '
first of all, about the experience props inside, my God, isn't this robbery? 1000? A week? 100 in a week
this is not a robbery. What is it? About free online games, fairness should be the minimum. It's too profit-making. Playing games is for fun, not for a machine that keeps throwing money into it. This is for most friends, but there are also those big bosses who spend more than 10 W RMB playing a game. Is it a money problem for this family? Is it a bit too... Black for national QQ? I can't think of any other words to describe
friends, especially those who come for free forever. Note: when you work hard every day, someone has already spent half of your time to finish it, and it's very relaxed. Although they have paid, is it too much? 100 yuan a week? Play a game of robbery under the banner of forever free? In many parts of China, this 100 yuan is the living expenses of a family of several people for half a year
secondly, experience is only a foundation, and the following is about equipment. Friends who have played Huaxia 2 all know that in Huaxia 2 life skills, there are several skills, such as mining, medicine training, refining, synthesis, refining, inlaying, and herbs. Mining is the most basic one, but there is no mining in QQ Huaxia. Why? What does it mean to have no mining? It means that your equipment and weapons are not refined. It means that the balance of the game will be affected again. It's people who play the game, not money. Instead of mining, prospecting requires you to pay the pocket money you earn or save, even if you have a mine, Well, please take a look at the prop "Tiangong and Samsara" in the prop store. People must know that there is something wrong with it, that is, without it, there is little chance for you to attach additional attributes to your weapon. Otherwise, why does he launch this prop
these two points are the key to your game's fate. Are you equipped, but it's a whiteboard. Even if you have a set of 6-dang's best attributes, in most cases, you can't pK a 5-dang-5 or above player of the same class level
not equipped? There's no grade. What do you play? Or rather, how to play
friends, please calculate that if you want to play well, you should invest 100RMB in a week, excluding others (PS: Huaxia map basically depends on running, rich people buy horses, and those without money rely on two legs, horses are not very expensive, cheap 1200 points, expensive 6000 points)!) If you can spend 100 on this one week, why not play "* next 2"? 100 a week, you can be sure to become the very import people of the server in a very short time
finally, I would like to remind you of one important thing: friends who play Huaxia 2 know that our players fight for the fees themselves, because we are also consumers, and consumers should have their own rights. If we really want to play for QQ Huaxia 2, For the sake of the players, please look at the price in the props mall. Is it the price that the price bureau can approve<
I hope my friends don't hold the idea that they are willing to fight and win, and fight for some rights for themselves
1 grade compass can be seen at tianyuansheng level 7 (mining level)
2 grade compass can be seen at excavation level 13 and 15
Xuanyuan 25 can be seen at
3 grade compass, Xuanyuan, xilie, 27 excavation
(mining is the most difficult when the ore source is not visible. It takes 1-2 hours for one proct, and it takes about 2 hours for 13-15 for two procts. You must bring back the city scroll with you, because tianshengyuan and the right city are in the middle of the map, so you have to take it even if you can see it. It saves a lot of time.
How can I get the compass, If the cold iron is not easy to sell, I suggest you take the copper formula. If it's easy to sell, it's much easier to sell the refined copper. What's the business? It's only when it can be circulated that you can make money
you need to collect the second grade compass as soon as possible. If you can receive it at 11j on the second day of the Development Zone, and many of them will arrive at 14J in a week, it's not easy to collect. The third grade compass is the most difficult to collect. As long as it's sold in the market, you can buy it. (if the price is too high, don't, or it will be higher in the future)
the price of the mine; I have observed for a period of time that some people rece their prices in order to sell them quickly. I don't think it's a good idea to stand on your feet. As long as it's not expensive, it's OK. The most important thing is the place to put the beach. I find that in the middle of tianyuansheng, it's the best place under the statue. It's the fastest place to buy. It's not easy to grab the stall. Sometimes it takes half an hour to put it on, but it's absolutely worth it
mining profit; One proct is good enough for capital, and the second proct is good enough for capital. Mo Yin earns money. The price of black gold doesn't rise and fall very much, and it's relatively short. (collect the formula of black gold early, and your profit of second proct is still large when Mo Yin drops to 10Y). The third proct of 6.7d mine is not only enough for cost. You have to go to the market every day before setting up a stall. If you dig the third proct first, you will be in charge of the market, So mining must be done early. If you dig three procts in four days in the Development Zone, you can earn 1500 + J. don't rush to dig three procts. There are not many people in need. Dig 20 procts a day to meet the market demand. Continue to dig 2 grades
official website, there are mines, distribution map ~
Level 1 mining runs in tianshengyuan, mining when you see a mine, you don't see what you go to mining
the iron ore of grade 1 is only 10 silver, and benzene is dying<
to level 2, it's time to upgrade while fighting monsters. Don't deliberately go mining '
first of all, about the experience props inside, my God, isn't this robbery? 1000? A week? 100 in a week
this is not a robbery. What is it? About free online games, fairness should be the minimum. It's too profit-making. Playing games is for fun, not for a machine that keeps throwing money into it. This is for most friends, but there are also those big bosses who spend more than 10 W RMB playing a game. Is it a money problem for this family? Is it a bit too... Black for national QQ? I can't think of any other words to describe
friends, especially those who come for free forever. Note: when you work hard every day, someone has already spent half of your time to finish it, and it's very relaxed. Although they have paid, is it too much? 100 yuan a week? Play a game of robbery under the banner of forever free? In many parts of China, this 100 yuan is the living expenses of a family of several people for half a year
secondly, experience is only a foundation, and the following is about equipment. Friends who have played Huaxia 2 all know that in Huaxia 2 life skills, there are several skills, such as mining, medicine training, refining, synthesis, refining, inlaying, and herbs. Mining is the most basic one, but there is no mining in QQ Huaxia. Why? What does it mean to have no mining? It means that your equipment and weapons are not refined. It means that the balance of the game will be affected again. It's people who play the game, not money. Instead of mining, prospecting requires you to pay the pocket money you earn or save, even if you have a mine, Well, please take a look at the prop "Tiangong and Samsara" in the prop store. People must know that there is something wrong with it, that is, without it, there is little chance for you to attach additional attributes to your weapon. Otherwise, why does he launch this prop
these two points are the key to your game's fate. Are you equipped, but it's a whiteboard. Even if you have a set of 6-dang's best attributes, in most cases, you can't pK a 5-dang-5 or above player of the same class level
not equipped? There's no grade. What do you play? Or rather, how to play
friends, please calculate that if you want to play well, you should invest 100RMB in a week, excluding others (PS: Huaxia map basically depends on running, rich people buy horses, and those without money rely on two legs, horses are not very expensive, cheap 1200 points, expensive 6000 points)!) If you can spend 100 on this one week, why not play "* next 2"? 100 a week, you can be sure to become the very import people of the server in a very short time
finally, I would like to remind you of one important thing: friends who play Huaxia 2 know that our players fight for the fees themselves, because we are also consumers, and consumers should have their own rights. If we really want to play for QQ Huaxia 2, For the sake of the players, please look at the price in the props mall. Is it the price that the price bureau can approve<
I hope my friends don't hold the idea that they are willing to fight and win, and fight for some rights for themselves
1 grade compass can be seen at tianyuansheng level 7 (mining level)
2 grade compass can be seen at excavation level 13 and 15
Xuanyuan 25 can be seen at
3 grade compass, Xuanyuan, xilie, 27 excavation
(mining is the most difficult when the ore source is not visible. It takes 1-2 hours for one proct, and it takes about 2 hours for 13-15 for two procts. You must bring back the city scroll with you, because tianshengyuan and the right city are in the middle of the map, so you have to take it even if you can see it. It saves a lot of time.
How can I get the compass, If the cold iron is not easy to sell, I suggest you take the copper formula. If it's easy to sell, it's much easier to sell the refined copper. What's the business? It's only when it can be circulated that you can make money
you need to collect the second grade compass as soon as possible. If you can receive it at 11j on the second day of the Development Zone, and many of them will arrive at 14J in a week, it's not easy to collect. The third grade compass is the most difficult to collect. As long as it's sold in the market, you can buy it. (if the price is too high, don't, or it will be higher in the future)
the price of the mine; I have observed for a period of time that some people rece their prices in order to sell them quickly. I don't think it's a good idea to stand on your feet. As long as it's not expensive, it's OK. The most important thing is the place to put the beach. I find that in the middle of tianyuansheng, it's the best place under the statue. It's the fastest place to buy. It's not easy to grab the stall. Sometimes it takes half an hour to put it on, but it's absolutely worth it
mining profit; One proct is good enough for capital, and the second proct is good enough for capital. Mo Yin earns money. The price of black gold doesn't rise and fall very much, and it's relatively short. (collect the formula of black gold early, and your profit of second proct is still large when Mo Yin drops to 10Y). The third proct of 6.7d mine is not only enough for cost. You have to go to the market every day before setting up a stall. If you dig the third proct first, you will be in charge of the market, So mining must be done early. If you dig three procts in four days in the Development Zone, you can earn 1500 + J. don't rush to dig three procts. There are not many people in need. Dig 20 procts a day to meet the market demand. Continue to dig 2 grades
6. Hello
if you are buying medicine before digging, then buy a compass. Dig in tianshengyuan
to level 15
use 2-grade compass
level 27 3-grade compass
this super money making
hehe!
if you are buying medicine before digging, then buy a compass. Dig in tianshengyuan
to level 15
use 2-grade compass
level 27 3-grade compass
this super money making
hehe!
7. It's usually 2 p.m. to open a new area. You need to rush to level 25 before 10 p.m. and send 3 white jades. Some people have to ask: what's the relationship between mining and sending jade? If it's too much, you need a level when you go to banquan and Xuanyuan. Otherwise, you will go back to the city before mining<
to get down to business:
grade 1 compass can be seen in tianyuansheng grade 7 (mining grade)
grade 2 compass right can be seen in grade 13 excavation 15
grade 3 compass can be seen in Xuanyuan, xilie and 27 excavation
(mining is the most difficult when the ore source is invisible, and it takes 1-2 hours for Grade 1 compass, The 13-15 of the second proct is about 2 hours, so you must bring back the city roll with you, because tianshengyuan and the right city are in the middle of the map, so you have to take it even if you can see it, which saves a lot of time.
how can I get the compass: the grocer of the first proct has cold iron and copper, which I suggest to deal with. It's not a time to make money. If it's hard to sell cold iron, I suggest you take copper formula, It's much easier to sell copper by refining words. What's business? You can only make money if you can circulate it
you need to collect the second grade compass as soon as possible. If you can receive it at 11j on the second day of the Development Zone, and many of them will arrive at 14J in a week, it's not easy to collect. The third grade compass is the most difficult to collect. As long as it's sold in the market, you can buy it. (if the price is too high, don't, or it will be higher in the future)
the price of the mine; I have observed for a period of time that some people rece their prices in order to sell them quickly. I don't think it's a good idea to stand on your feet. As long as it's not expensive, it's OK. The most important thing is the place to put the beach. I find that in the middle of tianyuansheng, it's the best place under the statue. It's the fastest place to buy. It's not easy to grab the stall. Sometimes it takes half an hour to put it on, but it's absolutely worth it
mining profit; One proct is good enough for capital, and the second proct is good enough for capital. Mo Yin earns money. The price of black gold doesn't rise and fall very much, and it's relatively short. (collect the formula of black gold early, and your profit of second proct is still large when Mo Yin drops to 10Y). The third proct of 6.7d mine is not only enough for cost. You have to go to the market every day before setting up a stall. If you dig the third proct first, you will be in charge of the market, So mining must be done early. If you dig three procts in four days in the Development Zone, you can earn 1500 + J. don't rush to dig three procts. There are not many people in need. Dig 20 procts a day to meet the market demand. Continue to dig 2 grades.
to get down to business:
grade 1 compass can be seen in tianyuansheng grade 7 (mining grade)
grade 2 compass right can be seen in grade 13 excavation 15
grade 3 compass can be seen in Xuanyuan, xilie and 27 excavation
(mining is the most difficult when the ore source is invisible, and it takes 1-2 hours for Grade 1 compass, The 13-15 of the second proct is about 2 hours, so you must bring back the city roll with you, because tianshengyuan and the right city are in the middle of the map, so you have to take it even if you can see it, which saves a lot of time.
how can I get the compass: the grocer of the first proct has cold iron and copper, which I suggest to deal with. It's not a time to make money. If it's hard to sell cold iron, I suggest you take copper formula, It's much easier to sell copper by refining words. What's business? You can only make money if you can circulate it
you need to collect the second grade compass as soon as possible. If you can receive it at 11j on the second day of the Development Zone, and many of them will arrive at 14J in a week, it's not easy to collect. The third grade compass is the most difficult to collect. As long as it's sold in the market, you can buy it. (if the price is too high, don't, or it will be higher in the future)
the price of the mine; I have observed for a period of time that some people rece their prices in order to sell them quickly. I don't think it's a good idea to stand on your feet. As long as it's not expensive, it's OK. The most important thing is the place to put the beach. I find that in the middle of tianyuansheng, it's the best place under the statue. It's the fastest place to buy. It's not easy to grab the stall. Sometimes it takes half an hour to put it on, but it's absolutely worth it
mining profit; One proct is good enough for capital, and the second proct is good enough for capital. Mo Yin earns money. The price of black gold doesn't rise and fall very much, and it's relatively short. (collect the formula of black gold early, and your profit of second proct is still large when Mo Yin drops to 10Y). The third proct of 6.7d mine is not only enough for cost. You have to go to the market every day before setting up a stall. If you dig the third proct first, you will be in charge of the market, So mining must be done early. If you dig three procts in four days in the Development Zone, you can earn 1500 + J. don't rush to dig three procts. There are not many people in need. Dig 20 procts a day to meet the market demand. Continue to dig 2 grades.
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