Seventh grade (next) science midterm examination paper

Note: There are three major problems in this volume. Full score 120, and the test time is 90 minutes.

First, multiple-choice questions (***80 points, 4 points for each small question)

1. The structure related to hearing in the inner ear is, ()

(a) vestibule (b) semicircular canal (c) eustachian tube (d) cochlea

2. The eye can produce bactericidal substances subsidiary structure is ()

(a) eyelid (b) conjunctiva (c) lacrimal gland (d) nasolacrimal duct

3. The strings are usually tuned before playing. When the sound is too high, it is necessary to adjust the tone of the strings in order to make the tone of the sound emitted by the strings lower ()

Some make it vibrate (). .

(a) tightness (b) tightness (c) frequency increase (d) frequency decrease.

4. Four students have different opinions when discussing the sound phenomenon, and the correct one is ().

(a) the speed of sound in various media is constant; (b) sound propagates at the maximum speed in vacuum,

(c) Air is the medium of sound. (d) People speak by vibrating their tongues.

5. In the light reflection phenomenon, if the incident angle decreases gradually, the reflected light will: ()

(1) gradually deviating from normal; (b) gradually approaching normal.

(c) No change (d) No judgment.

6. Among the following statements, the correct one is ()

(1) When a person walks into the mirror, the image of the person in the mirror gradually becomes larger.

(2) Using laser to calibrate a straight line makes use of the principle that light propagates along a straight line.

(c) The blackboard reflects light, because light is diffusely reflected at the reflection.

(d) Pinhole imaging is formed by reflection of light.

7. Standing by the pool and looking into the water, you can see: leaves floating on the water, fish swimming underwater, reflections of houses by the pool, and white clouds in the sky, among which () is formed by the refraction of light.

(a) Leaves (b) Fish (c) The reflection of the house (d) The reflection of white clouds.

8. When the light is obliquely incident on the parallel glass brick from the air, as shown in the figure, the correct one of the four light path diagrams is ().

9. As shown in the figure, it is a schematic diagram of reflection and refraction at the interface of light, magnetism and water. The following statement is true ()

(A)MO is incident light, ON is reflected light and OP is refracted light.

(B)NO is incident light, OM is reflected light and OP is refracted light.

(C)PO is incident light, OM is reflected light and ON is refracted light.

(D)PO is incident light, ON is reflected light and OM is refracted light.

10. Someone did an imaging experiment with a convex lens with a little defect around it, and the image he got on the screen was compared with that of a convex lens without defect ()

(a) The image has not changed.

(b) There are also defects around the imaging.

(c) The size, inversion and position of the image are unchanged, but slightly darker.

(d) Depending on the degree of defects, if there are many defects around, a complete image cannot be formed.

1 1. A car is driving at a constant speed on a flat highway at a speed of 50 km/h, then the following statement is correct ().

(a) the speed is 50 kilometers per hour.

(b) The distance traveled by the car is 50 km/h..

(c) The distance traveled by the car per hour is 50 kilometers per hour.

The distance traveled by this car is 50 kilometers per hour.

12. Which of the following phenomena cannot explain the existence of gravity ()

(a) The water in the cup can be poured into your mouth. (b) The river always flows downwards.

When the apple was ripe, it fell to the ground.

13. When swimming, when the hands and feet stroke backwards, people move forward, and the force that makes people move forward is ().

(a) the buoyancy of people (b) the force of hands and feet on water.

(c) Resistance of water (d) Forward force of water on hands and feet.

14. In the following phenomena: ① After the artillery is fired, the whole body retreats; (2) Knock the handle of the hammer and put the hammer firmly on the handle;

(3) Mature fruits fall off the trees; People don't stop at the finish line. The purpose of inertia is ()

①②③④

15. The following statement is incorrect ()

(1) If there is no gravity, the shot put thrown upward will not fall to the ground.

If there is no friction, the car can't move forward

If there is no air, the sunlight will not reach the ground.

(d) Without inertia, the long jump cannot be carried out.

16. The following friction is harmful ()

(a) Friction between the belt and the pulley when the pulley rotates.

(b) Friction between the brake pad and the rim during bicycle braking.

(c) Friction between rotating shaft and bearing during machine rotation.

(d) Friction between javelin and hand during run-up

17. An object moves in a straight line at a uniform speed under the action of a balancing force. If one of the forces suddenly disappears, the object will ()

(a) Stop exercising immediately.

(b) Still moving in a straight line at a constant speed.

The direction of movement must be changed.

(d) Linear motion is possible, but the speed is constantly changing.

18. Make the box with the weight of 100 Newton move at a uniform speed on the horizontal ground, the horizontal tension is 20 Newton, and the friction between the ground and the box is ().

(A) 120N(B) 100N(C)20N(D)80N。

19. When screwing the nut with a wrench, it is easier to tighten the nut by holding the end of the handle than by holding the middle of the handle. This shows that the function of force is the same as that of ()

(a) The magnitude of the force is related to the direction of the force (b).

(c) The point of action of the force is relevant. (d) The above three items are not related in any way.

20. When the car does which of the following sports, the motion state remains unchanged ().

(a) Moving from a standstill.

Turn on the highway.

Do uniform linear motion.

(d) Movement during the braking phase

II. Fill in the blanks (***32 points, 65438+ 0 points per grid)

2 1. When bees and mosquitoes fly, the buzz is generated by the wings _ _ _ _ _ _ _ _ _; The north wind whistling is the air in _ _ _ _ _ _ _; When the object sounds, it is in _ _ _ _ _ _ _. An object that usually vibrates and makes a sound is called _ _ _ _ _ _ _.

22. Light travels along _ _ _ _ _ _ in the same substance, and the speed of light propagation in vacuum is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

23. As shown in the figure, the incident light obliquely enters the interface of another medium from the air, and the reflected line is at right angles to the refracted line.

The incident angle is _ _ _ _ _ _ _ _ _, and the refraction angle is _ _ _ _ _ _ _.

24. When the doctor checked Zhang Hong's eyesight, Zhang Hong observed the eye chart through a flat mirror, as shown in the figure. The distance between Zhang Hong and the image in the chart is _ _ _ _ _. If you don't use a flat mirror and look at the eye chart directly, the distance between Zhang Hong and the eye chart should be _ _ _ _ _ _ _.

25. When light hits a smooth plane, the reflection phenomenon is reflection, and when it hits a rough plane, it is _ _ _ _ _ _ _. No matter what kind of reflection happens, every ray obeys the law of _ _ _ _ _ _ _.

26. On the optical bench, when doing the convex lens imaging experiment with candles, take _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

27. Stones thrown vertically upward are subjected to _ _ _ _ _ _ _ _ _ force in the process of rising, and the object of force is _ _ _ _ _ _ _ _ _ _ _ _. (regardless of air resistance)

28. There is an object weighing 20 cows on the scale of the horizontal platform scale, and the pointer of the platform scale is _ _ _ _ _ _ _ _ _ _ _ _ _; When the object presses down vertically with a force of 5 Newton, the pointer of the platform scale is _ _ _ _ _ _ _ _ _ _ _ _ _; When an object is pulled vertically with a force of 5 Newton, the pointer of the platform scale is _ _ _ _ _ _ _ _.

29. An object with a mass of 50 kg moves in a straight line along a horizontal table under the horizontal tension of 200 N, The friction force on an object is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ If the moving speed of an object increases, the friction force will be _ _ _ _ _ _ _ _ _ (select "increase", "unchanged" or "decrease").

30. The same piece of wood is placed on the same desktop, pulled by a spring scale, and moves at the same speed and uniform speed, as shown in the following figures A and B..

, the spring scale shows a larger number is _ _ _ _ _ _ _.

3 1. The picture shows the tennis racket hitting the ball. As can be seen from the picture, the ball and the racket are deformed, which shows two points: first, the force can make the object _ _ _ _ _ _ _ _ _ _ _; At the same time, the role of force is _ _ _ _ _ _. In addition, the motion of the ball changes when the racquet hits the ball, which shows that the force also changes the object.

3. Calculate and answer questions (***8 points, 4 points for each question).

32. The K 18 train from Harbin East Station to Beijing arrived in the evening, running at 1288km. The train schedule is as follows:

Harbin East Harbin Shenyang North Beijing

K 18 Arrival Time 20: 14 02: 23 09: 30

Departure time 20: 00 20: 32 02: 3 1

Find the average speed of the whole train.

33. As shown in Figure A, the taillight of a bicycle is a schematic sectional view, consisting of small flat mirrors at right angles to each other. Try to draw the reflected light on the picture and point out the ingenuity of this design.

Reference answer:1.d2.b3.bd4.c5.b6.b7.b8.a9.b11.d12.d/kloc-0.

2 1. vibration vibration: vibration sound source 22. The straight line 3× 108m/s is smaller by 23.60 degrees 30 degrees 24.5.4m0.4m25.. Specular diffuse reflection 26. The light screen height of the candle convex lens becomes lower. Heavy earthwork 28.20 25 15, 29.29.

The seventh grade science first semester midterm examination questions.

Volume 1 (multiple choice question ***50 points)

I. Multiple-choice questions: (There are 25 small questions in this big question, with 2 points for each small question and 50 points for * * *. Of the four options listed in each question, only one is the most suitable. Please choose and fill in the answer sheet in front of the H volume.

1, the water in the salt lake does not belong to:

A. Salt water B. Seawater C. Land water D. Surface water

2, more than two-thirds of the earth's fresh water is stored in:

A. Rivers B. Ponds and lakes C. Marshes D. Glaciers and icebergs

3, 97% of the earth's total water in ().

A. ice layer b atmosphere c ocean d groundwater

4, when using alcohol lamp, the highest temperature of alcohol lamp is:

Wick b, outer flame c, inner flame d and the part above the outer flame.

5. If you are asked to measure the density of a marble, which of the following is unnecessary:.

A. balance b, alcohol lamp c, measuring cylinder d and water.

6. The shape that sunlight sees on the ground through a diamond-shaped hole is.

A. diamond B. circle C. ellipse D. uncertainty

7, the following objects, does not belong to the light source is:

A. flashlight B. moon C. fluorescent lamp D. firefly

8, the red light is a red light, because:

A. the light source inside emits red light. B.people can only emit red light at night.

C. Only the red component in white light can pass through the lampshade D. None of the above statements is correct.

9, the reason for the solar eclipse is:

A, because light travels in a straight line, and the moon stands between the sun and the earth.

B.the sun suddenly stopped shining. Clouds block people's view.

D. The sun is blocked because the earth runs between the sun and the moon.

10, and the mass fraction of oxygen in the air is:

A.78% B.21%C.0.94% D. None of the above are correct.

1 1. The following description of air is incorrect:

A. Nitrogen in the air is usually colorless and odorless-

B. nitrogen and oxygen are the main components of air.

C. the composition of air is fixed.

D. air is not a single substance, but is made up of many gases.

12. When the fountain pen absorbs ink, squeeze the rubber hose on the pen several times and then loosen it, and the ink will be sucked into the rubber hose. This is because:

A, alarate was sucked up. Atmospheric pressure presses the ink up.

C. gravity sucks ink up. D. None of the above statements is correct.

13, the following statement about soil is correct:

① The loam contains the most sand. There are many kinds of animals living in the soil, and these animals will also have an impact on the soil.

(3) The most suitable soil for the growth of various plants is soil.

(4) The soil provides nutrients and water needed by plants, and plants make the soil more fertile.

A.①② B.③④C、①③ D.②④

After human beings have seriously damaged the vegetation on the sloping land, the surface soil is destroyed, the land-derived materials move, and the loss process is accelerated, that is, soil erosion occurs, including soil fertility decline, reservoir siltation, river bed elevation, navigation capacity reduction, flooding, and threats to the safety of industrial and mining transportation facilities. In high mountains and deep valleys, soil erosion often leads to landslides and mudslides, endangering industrial and mining traffic, life and property safety and deteriorating the ecological environment. Problems with reading materials 14- 16

14. What do you think is the main cause of soil erosion?

A, human destruction of vegetation B, volcano C, earthquake D, climate anomaly

15, the most serious soil erosion in the following areas is:

A. sloping land with grass B. bare sloping land C. wasteland full of weeds D. woodland full of fruit trees

16, the hazards of soil erosion and prevention measures are described correctly:

① Soil erosion reduces soil fertility; ② Soil erosion expands the existing cultivated land area.

(3) Afforestation is beneficial to soil and water conservation. (4) Soil erosion in northern grassland is the main cause of sandstorm in China.

A.①②③B.②③④C.①③④ D.①②④

17, about the description of the shape of the earth, the most scientific statement is:

A. The earth is round B. The earth is an ellipsoid with slightly flat poles and slightly bulging equator.

C. The earth is a regular sphere D. The earth is an irregular sphere with slightly flat poles and slightly bulging equator.

18, Wuhan is located in the east of Jianghan Plain. The following topographic sketches can correctly represent the topography of Jianghan Plain: ()

19, in terms of economic development, the advantages of mountainous areas are as follows:

A. Rich in resources and beautiful environment B. Vast land is beneficial to the development of agriculture.

C. rich in resources and convenient transportation D. humid climate and rich in species resources.

20, about the influence of human activities on the surface morphology, which of the following behavior is worth promoting:

A. Reclaim farmland around lakes, expand grain planting area, reclaim grasslands and develop grain production.

C. Build terraced fields on gentle slopes of hills, and develop farming. D. Destroy forests to open up wasteland and develop diversified management.

2 1 In the following four pictures, the position of point P is in the northern hemisphere, in the western hemisphere and in the low latitude area:

22. The following map drawing methods are correct: ()

23, the following contour topographic map, said the ridge is:

24. The description of contour topographic map is correct:

A. the heights of all points on the same contour line are equal. B Looking down from the top of the mountain, the bigger the coil, the bigger the value.

C The distance between contour lines is 0, which means that the slope of the surface is 0.

The smaller the distance between contour lines, the smaller the slope of the terrain.

25. In the contour map of different parts of the mountain below, the mistake is:

II. Fill in the blanks (65438+ 0 for each blank, * * * 30)

26. () One of the most basic substances needed for life, for human body, () contains more water.

In summer, compared with coastal areas, the temperature difference between day and night in China's inland areas is larger, because () the area occupied by the ocean on the earth's surface is (). Among them, fresh water accounts for 2 1.53% of the earth's surface water.

27. Thermometers and scales are commonly used measuring tools in daily life and production activities. For a thermometer, the temperature of the measured object cannot be higher than the temperature of the thermometer (). When measuring the temperature, the temperature ball should keep in contact with the measured object and read after (). The principle of thermometer is to use the property of liquid (). When using a balance to weigh the mass of a substance, first set () to 0, and then adjust () of the balance to balance the balance. When weighing an object, the general object is placed on the () plate, and () should be used to get the weight.

28, () and () are the main forms of solar energy. When sunlight passes through a prism, it can be divided into a colored light band, which is the phenomenon of (). When light hits the prism surface, part of the light will be (), which is called light reflection, and the other part will be () due to refraction.

29. The earth is surrounded by thick air. This air layer is called (), and 75% of the total air mass in the air layer is distributed within the nearest () kilometer from the ground. It is precisely because of the air layer that air has a () effect on objects on the earth's surface under the action of gravity. Due to the local temperature difference in the air layer, air flows, that is, () is formed.

30. Soil is composed of (), organic matter, air and water, and the content of () determines the fertility of soil.

3 1. According to the content of sand and clay in soil, soil can be divided into three types: sand, clay and topsoil. Think about the most suitable soil for growing rice in Jianghan Plain (). The most suitable soil for planting peanuts in Shandong hills is ().

32. China is a mountainous country, and the mountainous area accounts for about () of the total land area. Usually, mountains, hills and rugged () are collectively referred to as mountains.

33. The Three Gorges of the Yangtze River is formed by (), and Jianghan Plain is formed by ().

34. On a map with a latitude and longitude net, the direction should be determined according to the latitude and longitude lines, and the longitude line indicates () the latitude line indicates () the direction.

Third, comprehensive questions: (4 small questions, * * * 20 points)

35. The water on the earth is fresh water and salt water. How are they distributed? (3 points)

36. Please explain that the cork of thermos bottles without water often pops up automatically after a period of time? (3 points)

37, the Yellow River Basin map, answer the following questions (7 points)

(1) The main stream of the Yellow River flows from its source to the Bohai Sea, and the terrain areas it flows through mainly include the Qinghai-Tibet Plateau, the () Plateau, the Loess Plateau and the North China Plain.

(2) The surface morphology of the Loess Plateau is (). The reason for this surface morphology is ().

(3) The Yellow River is known as "a bowl of water, half a bowl of sand", and its high water content is caused by vegetation destruction on the Loess Plateau and heavy rain in summer. Therefore, the Yellow River is the main force in shaping the () plain.

(4) The Yellow River has become a world-famous river with high sediment concentration since its middle reaches. The key to harnessing the Yellow River lies in (). The fundamental measure to control the Yellow River flood disaster is ().

38. Read the contour map and answer the questions (7 points)

(l) The terrain name represented by the area where the letters are located in the figure is A. () B. () C. ().

(2) The relative height of two points of 2)DG is () meters. ..

(3) The extension direction of the highway is (), so the advantage of building a highway is ().

Four, additional questions (20 points)

Try to explain that in hot summer, you usually wear light clothes outdoors, but you usually wear dark clothes when you work indoors? (10)

40. During the summer vacation, three close classmates, A, B and C, traveled in the following areas. One day, A and C were talking on the phone and heard them say to C, "Oh, you are in East longitude 1700, 400 north latitude, and I am in West longitude 1700, 200 north latitude. Do you know where B is? Then he told me. What a coincidence! His current latitude and longitude position is right in the middle of our latitude and longitude. "

Answer the following questions according to the dialogue: (10)

(1) Mark the positions of A, B and C on the right picture.

(2) Among A, B and C, the one located in the Eastern Hemisphere is ().

(3)A, B and C are located at the middle latitude (), the low latitude () and the dividing line between the middle latitude and the low latitude () respectively.

(4) After the phone call, the three students are ready to meet, and the location is determined in the position of classmate B, so the direction of classmate A is ().

The direction of C is ().

(5) When A passed the Tropic of Cancer on the way forward, he suddenly found that his body shadow was gone, indicating that A arrived at this time at () and the sun was shining directly at ().

Answers to the midterm exam questions in the first semester of seventh grade science

1. 1 B2 D3 C4 b 5b 7b 8c 9a 10d 1c 12b 13d 14a。

15B 16D 17D 18B 19A 20C 2 1B 22D 23C 24A 25C

Under the same conditions, the temperature change of land is much greater than that of ocean. 9%

27 range indicator stable thermal expansion and cold contraction running code balance nut left and right 28 dispersion lamp and thermal light

Reflect off the original direction 29 atmosphere 18 barometric wind 30 mineral organic matter

3 1 Clay Sand 32 2/3 Plateau 33 Flowing Water Erosion Flowing Water Deposition 34 East, West, North and South

3.35 Most of the earth's water exists in salt water, accounting for 97% of the world's total water. 47%, salt water can not be directly drunk and irrigated. The total amount of fresh water in the world only accounts for 2.53% of the total water. Most of these fresh water exists in the form of glaciers and permanent snow, which cannot be directly used by human beings. The fresh water that can be directly used by human beings is river water, fresh lake water and shallow groundwater, and the total amount of these fresh water only accounts for about 0.3% of the total fresh water.

Water vapor continuously enters the air in the bottle, and the temperature of the air in the bottle rises. When the air pressure in the bottle is greater than the external atmospheric pressure, the bottle stopper will pop up.

37 (1) Inner Mongolia Plateau (2) Gully and gully soil erosion (3) Soil looseness in North China (4) Prevention and control of soil erosion and increase of vegetation (38) (1) Douyaling Valley (2) 100 (3) Southwest-Northeast Highway has a small slope and the cost of building the highway is low.

Because light clothes absorb less solar radiation than dark clothes, it is cooler to wear light clothes outdoors;

When the air conditioner is turned on indoors, the temperature is low, and dark clothes absorb more solar radiation than light clothes, so wearing dark clothes will not be too cold.

40.( 1) and (2) are not on the tropic of cancer, in the western hemisphere (3) at noon 12, CA B (4), and things (5).