How to calculate the force between permanent magnets

1.

Let the air gap magnetic density BG, magnetic field strength Hg, air gap area Ag and air gap length LG, then the attractive force F is:

F = BG * Hg * Ag / 2

that is, the magnetic force between the magnet and the armature is proportional to the air gap magnetic density, magnetic field strength and air gap area. See the following

for details

2. This is a very complex problem, so I won't mention it before high school, even college physics doesn't have it (college physics only has the calculation method of magnetic field generated by current, but magnet doesn't), unless it is a related major.. This is related to some properties of the magnet itself, the shape of the magnet, the magnetic medium in the middle (whether there is ferromagnetic material in the middle), and whether there is magnetization. There may be some empirical formulas for magnets with fixed shape and strength
I only know how to calculate the torque of the motor. As for me, I think it's difficult to calculate the torque of the motor for non related majors. It's more complicated because only very close can there be a force. If it's very close, it's necessary to carry out triple integral calculation according to the shape. It's very troublesome, and it's even more difficult to calculate if the shape is irregular....

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4.

Name and address of Shanghai Legal Aid Center: 5th floor, Lane 1, Lane 268, xiaomuqiao Road, Shanghai Legal Aid Center (near Xietu intersection); 1st floor, Lane 2, Hehuan Road, Pudong New Area Legal Aid Center (Pudong Citizen Center); 1st floor, Lane 2, Lane 380, Tianyaoqiao Road, Xuhui District Legal Aid Center (near Nandan Road); 3rd floor, Lane 518, Zhaohua Road, Changning District Legal Aid Center (near Dingxi Road) No.1980 Dahe Road, Putuo District Legal Aid Center (near Zhichuan Road); No.15 Lane 610, Daning Road, Zhabei District Legal Aid Center (near Gonghexin Road); No.20 Lane 421, Siping Road, Hongkou District Legal Aid Center (near Quyang Road); no.583 Yangzhou Road, Yangpu District Legal Aid Center (near Qiqihar Road); No.288 Guohuo Road, Huangpu District Legal Aid Center (near Puyu West Road) Bay Area Legal Aid Center, no.7-8, Lane 410, Ruijin 2nd Road (near Taikang Road), room 1002, 969 Wuding Road, Jing'an District Legal Aid Center (between Jiaozhou Road and Changde Road), no.218, Lane 300, Youyi Branch Road, Baoshan District Legal Aid Center (near Pangu intersection), No.384, Xintan Road, Minhang District Legal Aid Center, No.85, Jinsha Road, Jiading District Legal Aid Center (near Bole Road), Jinshan District Legal Aid Center Legal Aid Center No.362 Banqiao West Road (near Mengshan Road) Songjiang District Legal Aid Center No.153 Renmin North Road (near Zhongshan Second Road) Qingpu District Legal Aid Center No.76 Yixian street, Qingpu Town (near Chengzhong North Road) Chongming County Legal Aid Center No.76 hanshanshansi Road, Chengqiao town (near Renmin Road) Fengxian District Legal Aid Center No.6 Meiqi Road, Nanqiao town (near Chengzhong North Road) 1705 Nanfeng highway)

5. "12348" is a special telephone for legal consultation of Shanghai Judicial Bureau and Shanghai Legal Aid Center. It receives legal consultation from the masses, coordinates with the mediation of civil disputes, timely reflects the legal needs of the masses, guides and accepts legal aid applications, and protects the legitimate rights and interests of the weak parties, judicial justice and social stability<

list of Shanghai Legal Aid Center

Shanghai Legal Aid Center

200032, 5th floor, Lane 268, xiaomuqiao road

64221522

9:00-11:30, 1: 30-4:00 Monday to Friday

Pudong New Area Legal Aid Center

Room 111, building 2, 141 Pudong Avenue, 200120

58796080

9:00-11:30, 1:30-4:30 Monday to Friday

Hongkou District Legal Aid Center

No. 20, Lane 421, Siping Road, 200081

65074142

9:00-11:30, 2: 00-4:30 Monday to Friday

no.7-8, Lane 410, Ruijin 2nd Road, legal aid center, Luwan District, 200020 64450665, 8:30-11:30, 1:00-4:00 Monday to Friday

No.15, Lane 610, Daning Road, legal aid center, Zhabei District, 200072 56774044, 9:00-11:30, 1: 30-5:00 Monday to Friday

no.583 Yangzhou Road, Yangpu District Legal Aid Center, 200082 65895194, 9:00-11:00, 1:30-4:00 Monday to Friday

Huangpu District Legal Aid Center

1100 Lujiabang Road, B 200003

63761789

9:00-11:00, 1: 30-4:00 Monday to Friday

Xuhui District Legal Aid Center

Room 101, No.8 Lane 591, Hongqiao Road (near Panyu intersection), 200233

64472834

9:00-11:30, 1:30-4:30 Monday to Friday

Jing'an District Legal Aid Center

No.106, No.15 Lane 123, Yanping Road, 200040

62720643

9:00-11:00, 1: 30-4:00 Monday to Friday

Baoshan District Legal Aid Center

friendship Branch Lane 300 201900

36070223

8:30 pm to 4:30 pm Monday to Friday

Songjiang District Legal Aid Center

181 Renmin North Road 201600

67721363

8:00-11:30, 1: 00-5:00 Monday to Friday

Changning District Legal Aid Center

No.3, Lane 518, Zhaohua Road, 200042

62527835

9:00-11:30, 1: 30-4:30 Monday to Friday

Putuo District Legal Aid Center

Dahe road 1717 200063

62659499

8:30 a.m. - 5:30 p.m.
Monday to Friday

Qingpu District Legal Aid Center

No. 76, Yixian street, Qingpu Town 201700


59735110

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Jinshan District Legal Aid Center

129 Xiangzhou road 200540

57943149

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Jiading District Legal Aid Center

70-3 Bole South Road 201800

69985448

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Minhang District Legal Aid Center

303 Xinsong Road, 201100

54955148

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Nanhui District Legal Aid Center

88 Renmin West Road, Huinan Town, 201300

58010606

8:30-11:30, 1: 30-4:30 Monday to Friday

legal aid center of Fengxian District

no.1705 Nanfeng Road, Nanqiao Town, 201400

37110205

8:00-11:30, 2:00-5:30 Monday to Friday

legal aid center of Chongming County

No.8 Renmin Road, 202150

59610253

8:00-11:30, 1: 00-5:00 Monday to Friday

municipal staff legal aid center

No.14, Zhongshan East 1st Road 200002

63212202

9:00-11:30, 1:30-4:30 every Tuesday and Wednesday

Municipal Legal Aid Center for the elderly

No.8, Lane 520, Yuyuan Road 200040

62250169

9:00-11:30, 1:30-3:30 every Monday, Wednesday and Friday 5

Municipal Women's Legal Aid Center

No.245, Tianping Road, 200030

64379269

9:00-11:30, 1:30-4:30 Monday to Thursday

Municipal Legal Aid Center for the disabled

No.50, Hankou Road, 200002


63230172

1:30-4:30 every Monday and Wednesday

6. Legal aid is a legal guarantee system that legal aid institutions established by the government organize lawyers or legal service workers to provide free legal services for people with financial difficulties or special cases. Special cases refer to cases in which, according to Article 34 of the criminal procere law of the people's Republic of China, the defendant in a criminal case is blind, deaf or mute, or a minor has not entrusted a defender, or the defendant may be sentenced to death but has not entrusted a defender, and shall receive legal aid

legal aid is a social public welfare undertaking to help the poor and the weak and protect the legitimate rights and interests of the vulnerable groups. It is also an important measure for China to practice the strategy of ruling the country by law and build a well-off society in an all-round way. The Central Committee of the Communist Party of China and the State Council attach great importance to the work of legal aid. The outline of the tenth five year plan sets "establishing a legal aid system" as the social development goal of the tenth five year plan. The 16th National Congress of the Communist Party of China clearly puts forward "actively developing legal aid" as an important content of building socialist political civilization The promulgation and implementation of the regulations on legal aid and the development of the large-scale public welfare activities of "legal aid in China for the sake of fairness and justice" mark a new development and breakthrough in the breadth and depth of China's legal aid work
in current China, there are still a group of people or strata who are in a disadvantageous social position because of the low natural, economic, social and cultural status, and are difficult to solve the pressure caused by social problems like normal people, which is also the so-called vulnerable groups. As an important part of the judicial system, legal aid provides legal help to those parties who are lack of ability and financial difficulties, so that they can stand before the law equally and enjoy equal legal protection. Legal aid system is the inevitable proct of the development of human legal civilization and legal culture to a certain stage, and the result of the progress of national economy and social civilization and the enhancement of the concept of rule of law. To help the people solve the problem of litigation difficulty by legal means is an inevitable choice under the background of building a socialist country ruled by law and an important guarantee to promote judicial justice.

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8.

Hello, building owner:

bus line: Subway Line 1 → No.113, the whole journey is about 16.5km

1. Walk about 590m from Taihe Road to Gongfu Xincun station

2. Take subway line 1, pass 9 stations to Shanghai railway station

3. Walk about 50m to Shanghai railway station (South Square) station

4. Take No.113, pass 4 stations to Changde Road Station of Changping Road

5 Walk about 400 meters to the legal aid center of Jing'an District

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