Chapter vi

I. Lens

Convex lens: it can condense light.

Concave lens: it has divergent effect on light.

Focus: the light parallel to the main optical axis passes through the convex lens and converges at point F, which is called the focus of the convex lens.

Focal length: The distance from the focal point to the optical center of the convex lens is called focal length.

The smaller the focal length of the lens, the more obvious the convergence (or divergence) effect.

2. The imaging law of convex lens.

Attribute of object distance image

Stand upright or upside down to enlarge or reduce a virtual image or a real image.

U & GT2F2 & GTV> Inverted Restore Real Image

U=2f v=2f inverted image.

2f>u>f v & gt2f Inverted Enlarge Real Image

U<f is enlarging the virtual image.

Three. Ordinary lens

1. Slide projector and projector

Imaging characteristics: When an object is between one focal length and two focal lengths of a convex lens, it becomes an inverted magnified real image.

Note: Slides should be placed upside down.

2. camera

Imaging object point: the object is out of the double focal length of the convex lens and inverted and reduced.

magnifier

Imaging characteristics: the object is in a vertical magnified virtual image within a focal length of the convex lens. The object is on the same side as the image.

Four. eye

From the imaging point of view, the human eye can be simplified as a convex lens and a screen.

Apparent distance: The image formed by an object at a distance of 25cm from the eyes is the clearest, so the distance of 25cm is called the apparent distance of normal eyes.

Myopia: The apparent distance is less than 25cm, and it can be corrected with concave lens.

Hyperopia: the apparent distance is greater than 25cm, and can be corrected by wearing a convex lens.

Glasses degree = 1/f× 100 (f must be in m). )

Chapter VII

I. Basic concepts:

1. Force is the action of one object on another. The forces between objects are mutual.

2. the symbol of force: F.

Unit of force: Newton; ordinary

3. The function of force: it can change the motion state of the object; Can change the shape of an object.

4. Dynamometer: dynamometer. (Spring dynamometer used in laboratory)

5. The three elements of force: the size, direction and action point of force.

The method of representing all three elements of force with line segments with arrows is called force diagram.

Two. gravity

1. The force that an object near the ground receives due to the gravity of the earth is called gravity.

Force object: the earth.

2. Gravity direction: vertical downward.

The gravity of an object is directly proportional to its mass.

G = mgg is 9.8N/kg, that is to say, the gravity of 1kg is 9.8N. ..

Three. rub

1. The force generated in the process of sliding friction is called sliding friction.

2. Factors of sliding friction: pressure; Roughness of contact surface.

3. Direction of sliding friction: opposite to the direction of motion of the object.

4. The method of increasing friction:

Increase the pressure; Roughening the contact surface;

Ways to reduce friction:

Relieve stress; Smooth the contact surface.

4. Two-force synthesis on the same line.

Same direction: F=F 1+F2.

Opposite direction: f = f1-F2 (f1> F2)

Verb (abbreviation for verb) is the balance of two forces.

1. An object is in a state of static or uniform linear motion, which is called balance. The force acting on a balanced object is called a balanced force.

2. If only two forces of an object are in equilibrium, it is called two-force equilibrium.

3. Conditions for the balance of two forces: If two forces acting on the same object are equal in magnitude and opposite in direction and act on the same straight line, we say that the two forces are in balance with each other.

When a balancing force is applied, the resultant force on the object is zero. Under the action of balancing force, the motion state of the object remains unchanged.

6. Newton's first law

1. When no external force acts on all objects, they always keep moving in a straight line at a uniform speed or at rest. This law is called Newton's first law, also known as the law of inertia.

2. The invariability of the moving state of an object is called inertia.

Chapter VIII

I. Stress

1. The force acting vertically on the surface of an object is called pressure.

2. The function of pressure: deform the object.

3. Influencing factors of pressure effect: the magnitude of pressure; The size of the stress zone.

4. Pressure direction: downward perpendicular to the contact surface.

Two. pressure

1. Meaning: a physical quantity indicating the influence of pressure.

2. Definition: The pressure acting on the unit area of an object is called pressure.

3. Formula: p = f/s; (Pressure = pressure/stressed area)

4. Unit: Pascal. protactinium

1pa = 1n/m2, which means that the pressure per square meter is 1n.

5. Ways to increase pressure:

Constant pressure reduces the stress area;

The stress area is fixed and the pressure increases.

6. Ways to reduce stress:

When the pressure is constant, the stress area increases;

The stress area is fixed, so the pressure is reduced.

Three. Internal pressure of liquid

1. Causes of internal pressure of liquid: liquid is subjected to gravity and has fluidity.

2. The law of liquid internal pressure:

(1) There is pressure in all directions in the liquid;

(2) At the same depth in a liquid, the pressure of the liquid is equal in all directions;

(3) The internal pressure of liquid increases with the increase of depth;

(4) The pressure inside the liquid is related to the density of the liquid.

3. Calculation formula of liquid internal pressure: p =

4. Communicator: A container with an open top and a connected bottom is called a communicator.

Features of the communication device: If there is only one liquid in the communication device, when the liquid is still, the liquid level in each container of the communication device is always flat.

Application of communicator: sewer return pipe; Water tower water supply system; Water level gauge; Automatic drinking fountain for livestock, etc.

Four. atmospheric pressure

1. There is pressure in all directions in the air, and this pressure is called atmospheric pressure.

2. A famous experiment to prove the existence of atmospheric pressure: the Madeborg Hemisphere Experiment;

Experiment of measuring atmospheric pressure: Torricelli experiment.

3. 1 standard atmospheric pressure = = 760mmhg (generation pressure) =1.01×105pa.

4. Factors affecting atmospheric pressure

① Atmospheric pressure decreases with the increase of height; (Within 2000m above sea level, the atmospheric pressure will drop by about 1 33pa (1mmHg) for every increase of12m.

(2) Under the condition of constant temperature, the volume of a certain mass of gas decreases, the pressure increases, the volume increases and the pressure decreases.

③ Atmospheric pressure is also related to weather, temperature and other conditions.

5. The application of atmospheric pressure:

Piston pump; Diesel engine driven centrifugal water pump

Outline of geography review in the second semester of junior high school (new textbook)

Chapter 5:

1, there are many different types of geographical areas, some are natural areas, such as the Pearl River Delta; Some are economic zones, such as industrial zones; Some are administrative districts, such as Xizang Autonomous Region. The same geographical area may have multiple identities at the same time.

2. According to the different geographical location, natural and human geographical features, China can be divided into four geographical regions, namely, northern region, southern region, northwest region and Qinghai-Tibet region. Among them, Qinling Mountain and Huaihe River are the dividing lines between the northern region and the southern region.

3. There are obvious differences in topography, climate, river flow and vegetation types between the north and the south of China. Affected by the natural environment, people in the north and the south also have great differences in production methods, living habits and cultural traditions.

Comparison of differences between south and north of China:

Qinling-North of Huaihe River-Qinling-South of Huaihe River Comparison Project

1 (higher/lower than 0) The monthly average temperature is lower than 0 and higher than 0.

The annual precipitation is small.

The main terrain is dominated by plains and plateaus, and plains, basins, plateaus and hills crisscross.

Vegetation type temperate deciduous broad-leaved forest subtropical evergreen broad-leaved forest

The river flow is small and large.

Farming system: one crop a year or three crops a year or two crops a year.

Cultivated upland paddy field

Cereal crops wheat and rice

Traditional means of transportation, carriages and boats

Traditional sports include skiing, skating, dragon boat racing and swimming.

4. The topography of northwest China is mainly plateaus and basins. The eastern part is dominated by grassland and desert landscape; There is a large area of desert in the western basin; Only rare oases appear at the edge of the basin. All these show that the northwest region is a region with drought as its main natural feature.

5. Qinghai-Tibet region is a unique region because of its high terrain, and another obvious natural feature that comes with "high" is "cold".

6. Northwest China and Qinghai-Tibet are the main pastoral areas in China. Inner Mongolia is mainly temperate grassland pasture; Xinjiang is mainly mountainous pasture; Qinghai and Tibet are mainly alpine pastures. Three rivers and three cows in Inner Mongolia, fine wool sheep in Xinjiang, yak in Qinghai-Tibet, Tibetan sheep and Tan sheep in Ningxia are all famous livestock breeds.

7. In addition to animal husbandry, people in northwest China also use river water and meltwater from alpine snow and ice to develop irrigated agriculture.

Chapter VI:

1. Beijing is the political and cultural center of the whole country and the center of international exchanges. The Great Hall of the People is the seat of the NPC Standing Committee, and Zhongnanhai is the seat of the Central Committee of the Communist Party of China and the State Council.

2. The urban pattern of the Forbidden City in Beijing is "convex", which is the representative work of the planning and construction of China's historical capitals.

There are countless places of interest in Beijing, such as the Great Wall, the Summer Palace, the Temple of Heaven and Zhoukoudian Peking Man Site.

Among them, the Forbidden City in Beijing is the largest and most well-preserved palace complex in the world.

4. In order to enhance international competitiveness and service functions, on the one hand, Beijing has intensified infrastructure construction, and planned and built key functional areas including the Central Business District and the International Media Avenue, as well as urban rapid rail transit and expressways; On the other hand, actively develop high-tech industries, improve urban management efficiency and service quality, and build a harmonious urban environment between people and the environment.

5. Hong Kong consists of Hong Kong Island, Kowloon Peninsula, New Territories and more than 200 surrounding islands, while Macao consists of Macao Peninsula, Taipa Island and Coloane Island. Hong Kong and Macao are among the regions with the highest population density in the world.

6. Hongkong and Macau are two special administrative regions of China. Our government has formulated the policy of "one country, two systems", and China's mainland implements the socialist system, while Hong Kong and Macao implement the capitalist system.

7. Hong Kong has a large population but a small population. "Going to heaven"-building tall buildings and "going to sea"-reclaiming land from the sea have become two important ways for Hong Kong to expand its urban construction land.

8. The tertiary industry in Hong Kong and Macao is very developed. Hong Kong is an international trade center, transportation center, financial center, information service center and tourism center. Gambling tourism is an important pillar industry of Macao's economic development.

9. For a long time, Hong Kong and Macau have maintained close economic ties with the mainland of China, especially Hong Kong. Mainland China is rich in natural and labor resources, and Hong Kong is rich in capital, technology, talents and management experience. The economic cooperation between Hong Kong and the mainland of China is complementary and mutually beneficial.

10, entrepot trade refers to the form of trade in which goods purchased from one country are sold directly to other countries instead of being sold locally. Mainland China is Hong Kong's largest entrepot trading partner.

1 1. Taiwan Province Province includes Taiwan Province Island, and many small islands such as Penghu Islands and Diaoyu Islands nearby. Taiwan Province Island is the largest island in China, bordering the East China Sea in the north, the Pacific Ocean in the east, the South China Sea in the south and Fujian Province across the Taiwan Province Strait in the west.

12, Taiwan Province Island is a rich treasure island, known as "the pearl of the southeast sea of the motherland". About half of the land on the island is covered with dense forests and has the reputation of "Asian Natural Botanical Garden". Cinnamomum camphora is the most famous tree species in Taiwan Province Province, and its camphor production ranks first in the world.

13. Before the 1960s, the economy of Taiwan Province Province was dominated by agriculture and agricultural products, exporting cane sugar, pineapple, rice and camphor. Since 1960s, Taiwan Province Province has focused on developing export processing industry, forming an "import-processing-export" economy.

14, Xinjiang Uygur Autonomous Region is the largest province in China. The mountains and basins in Xinjiang are distributed alternately, forming the topographical features of "three mountains and two basins". The majestic Tianshan Mountains span the central part of Xinjiang, with Tarim Basin and Junggar Basin on the north and south sides respectively.

15. There are thousands of oases in Xinjiang, which is the most important agricultural production base. Wheat, corn and sorghum are the main crops here, and cotton, sugar beet and various melons and fruits have become the characteristic agricultural products of Xinjiang Oasis. Karez is an ancient water diversion project, which has been used by oasis residents in Xinjiang for a long time.

16, the predicted oil and gas reserves in Xinjiang account for about 1/3 of the total land reserves in China. With the gradual implementation of the national energy strategic decision of "stabilizing the east and vigorously developing the west", Xinjiang is expected to become an important oil and gas industrial base in China. The implementation of the West-to-East Gas Transmission Project will rapidly increase the local fiscal revenue and alleviate the energy shortage in the eastern region.

Chapter 7:

1. The Pearl River Delta is located in the southeast of Guangdong Province, with convenient land and water transportation, and is known as the "South Gate" of China.

The Pearl River Delta region has formed a multi-level open system including special economic zones (Shenzhen and Zhuhai), coastal open cities (Guangzhou) and economic open areas (the whole Pearl River Delta).

2. Taking advantage of the superior conditions here, the Pearl River Delta has attracted a lot of overseas Chinese investment (the main source of foreign investment in the Pearl River Delta is Hong Kong and Macao) and has become the frontier of China's opening up.

3. Since 1980s, the Pearl River Delta has taken advantage of its superior geographical position adjacent to Hong Kong and Macao, accepted the industrial diffusion of Hong Kong and Macao nearby, introduced a large number of foreign capital, introduced advanced technology and equipment, management methods and the latest industrial and commercial science and technology information, established a large number of processing and manufacturing enterprises, and developed an export-oriented economy.

The products produced in the Pearl River Delta are mainly exported to Southeast Asia, Europe, Africa, America, Oceania and other regions through Hong Kong and Macao trade channels, earning a lot of foreign exchange. By the end of the 20th century, it has become one of the largest production and export bases of electronic and daily consumer goods in the world.

5. The cooperation between Hong Kong, Macao and the Pearl River Delta region is based on "store in front and factory in back". Hong Kong uses the overseas trade window to conduct marketing and external sales, and plays the role of "shop". The Pearl River Delta region takes advantage of land, natural resources and labor force to process, manufacture and assemble products, and plays the role of "factory".

6. The development of processing and manufacturing industry in the Pearl River Delta has promoted the development of service industries such as catering, entertainment and transportation. These non-agricultural industries provide a large number of employment opportunities for local surplus labor and also absorb millions of foreign labor.

7. With the development of non-agricultural industries and the migration of population, more and more agricultural land in the Pearl River Delta has been transformed into industrial, transportation and urban construction land. These non-agricultural land is adjacent to the remaining agricultural land, forming a unique land use landscape with staggered distribution of residential land, industrial land, infrastructure land and agricultural land.

8. Xishuangbanna is the most intact place in China's pristine tropical rain forest except Hainan Province. The towering trees, huge packing, cruel strangled plants and majestic "single tree into forest" are all unique landscapes of the rainforest.

There are thousands of animals living in Xishuangbanna, including Asian elephants, green peacocks and other national key protected animals. People vividly call it "the kingdom of tropical animals".

10, Xishuangbanna is still a place where ethnic minorities live in concentrated communities, and the multi-ethnic customs with Dai as the main body have added infinite charm to Xishuangbanna.

1 1. For a long time, Xishuangbanna has been dominated by agricultural production. Since the mid-1980s, with the encouragement of the relevant policies of the state and Yunnan Province, Xishuangbanna, with its unique location and resource advantages, has made tourism rise rapidly and become an important pillar industry.

Chapter 8:

1. The largest loess accumulation area in the world is the Loess Plateau, which is one of the areas with the most serious soil erosion in the world.

2. Soil erosion takes away the fertile soil on the surface and reduces the crop yield; Increase, expand and deepen the valley, thus reducing the cultivated land area; It also transported a lot of sediment to the lower reaches of the Yellow River, which caused great difficulties in river regulation and flood control.

3. The loess plateau has a broken terrain and a relatively dry climate, which not only causes serious soil erosion, but also causes frequent natural disasters. Drought and flood disasters are the most important natural disasters in the Loess Plateau, so the ecological environment of the Loess Plateau is very fragile.

4. In order to realize the sustainable development of social economy in the Loess Plateau, we must strengthen ecological construction and improve the environment. On the one hand, biological measures such as planting trees and grass should be combined with engineering measures such as terraced fields and earth dams to control soil erosion; On the other hand, reasonable arrangements should be made for production activities, such as returning farmland to forests and grasslands on steep slopes, and reducing the number of grazing livestock in overgrazing areas.

5. The area along the Yangtze River is a typical "banded" area, which is not only superior in geographical position, but also endowed with unique natural conditions, laying a solid foundation for the development of this area and being the center of national economic development.

6. The Yangtze River along the Yangtze River connects the economically developed coastal areas with the resource-rich western areas, forming an English letter "H" pattern, which is the link between the east and the west.

7. The area along the Yangtze River is an important agricultural area in China with a solid industrial base. At present, it has developed into one of the most dynamic high-tech industrial development zones in China. Through many north-south tributaries and traffic arteries, these economic and technological advantages can radiate north and south, and make China's north-south economy integrate.

8. There are many cities along the Yangtze River, with dense towns in the middle and lower reaches and few cities in the upper reaches. Among them, Shanghai, Nanjing, Wuhan and Chongqing are regional economic, cultural and transportation centers, which have a strong radiation and driving role in regional economic development. On the basis of these four megacities, four urban agglomerations centered on them have been formed respectively.

9. The Yangtze River is a highly developed comprehensive industrial zone in China. At present, four industrial bases have been formed from east to west. There are industrial bases such as steel, petrochemicals, automobiles and textiles along the Yangtze River, which constitute the embryonic form of China's east-west "industrial corridor".

10. During the development along the Yangtze River, a series of ecological and environmental problems have emerged, such as soil erosion, flood disaster (the middle and lower reaches of the Yangtze River are the most concentrated, serious and frequent areas of flood disaster in the Yangtze River basin), water pollution, acid rain and so on.

1 1. Acid rain will lead to acidification of water and soil, causing corrosion hazards to plants and buildings. The acid rain area in Central China is the largest acid rain pollution area with the highest central intensity in China, and the acid rain area in Southwest China is the second most serious acid rain area. The pollution intensity in East China is lower than that in Central China and Southwest China.

Chapter 9:

1, with vast territory and great regional differences, is a basic national condition of our country. To achieve sustainable development, a region needs to develop its economy according to local conditions and strengthen the ties between regions.

2. A large population and a low per capita GNP is another basic national condition of our country. The world in the 21st century is a world of economic globalization. China should actively integrate into the process of economic globalization and seek development in the world.