Eight grade physics, biology, geography, politics and history English examination paper. More than 2 sets, plus 5 points for one more set.

Eighth grade physics examination paper

(Time 100 minutes, total 100 minutes)

The total score is one, two, three, four and five. observer

1. Different instruments play the same music at the concert, and people can also distinguish the sounds made by different instruments. This is mainly based on ().

A. tone b loudness c timbre d frequency

2. As shown in the four scenes, the phenomenon of light reflection is ().

3. The statement about the circuit is wrong ()

A. the power supply is a device that provides electric energy.

B. Only when the circuit is closed will there be current in the circuit.

C. the current flows along the direction of "positive electrode-electric appliance-negative electrode"

D. Electrical appliances are devices that convert other forms of energy into electrical energy.

Winter in the north is really beautiful. Mao Zedong, a great man of a generation, once wrote the poem "The scenery in the northland is frozen for thousands of miles, and the snow is drifting in Wan Li. Looking at the inside and outside of the Great Wall, it is only boundless", in which the formation of ice belongs to the change of material state ().

A. solidification B. melting C. liquefaction D. sublimation

5. The object can form an inverted and reduced real image on the light screen through the convex lens. Which of the following optical instruments applies this formation principle ()?

A. camera B. magnifying glass C. slide projector D. car rearview mirror

6. Xiaoming blocked the red filter (that is, red glass) in front of the camera lens to shoot a yellow rose. The color of the flowers in the picture is ().

A. Yellow flowers B. Red flowers C. Black flowers D. White flowers

7. Among the following school supplies, the one that normally belongs to the conductor is ().

A. plastic scale B. small metal blade C. painting eraser D. physics textbook

8. The following measures to control noise, belong to prevent noise is ().

A. Turn the phone to mute during the meeting.

B. Close the doors and windows of the room

C. The houses beside the expressway are all equipped with sound-proof windows.

D. airport runway workers use noise-proof earmuffs

9. The light source of the projector in the classroom is a powerful light bulb, and the fan must be used to dissipate heat when it shines. When using the projector, it is required to start the motor driving the fan first, and then let the bulb shine; If the fan doesn't start, the light bulb won't shine. The following circuit diagram can meet the requirements is ()

10. Measure the working current of the bell with an ammeter. The following circuit diagram design is correct ().

1 1. The following statement about state change is true ().

The moth balls used for insect control become smaller with time, which is a melting phenomenon.

B. In summer, when the popsicle is unpacked, you will see "white steam", which is a sublimation phenomenon.

C. Small dewdrops appear on flowers and plants in autumn morning, which is liquefaction.

D. clothes frozen outdoors will also dry in winter, which is a vaporization phenomenon.

Reason for choosing: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

12. The following statement about convex lens is correct ().

A. An object image formed by a convex lens can be received by a light screen.

Convex lenses can be used to correct myopia.

C convex lens can condense light, so the image formed by the object through the convex lens is always reduced.

A convex lens can be a positive image or an inverted image.

Reason for choosing: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Three. Fill in the blanks (each blank 1, *** 17)

13. The common liquid thermometer is made according to the _ _ _ _ _ _ law of liquid. The reading of the thermometer in the figure is _ _ _ _℃. The scale value of the thermometer in the figure is _ _ _ _ _ _ _℃

14. In the hot sun, Shanghai World Expo Park started the fog-sen cooling system to relieve the temporary sweltering heat. The system automatically sprays water mist into the air. In the process of _ _ _ _ _ _ _ _ (fill in the name of material state change), the water mist generates a lot of heat from the surrounding environment, resulting in an obvious environmental temperature of _ _ _ _ _ _ _ _ _.

15. The projection screen in the multimedia classroom is made of rough white cloth, which has the following advantages: First, students in all seats in the classroom can see the picture by using _ _ _ _ _ _ _ _ _ _; Second, white cloth can reflect _ _ _ _ _ color light, so that students can see pictures with normal colors.

16. When Xiao Ming observes an object, the schematic diagram of the object imaging in the eyeball is as shown on the right, so Xiao Ming has _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

17. The connection mode between all appliances in the home circuit belongs to _ _ _ _ _ _ _; Between the switch and the controlled light bulb belongs to _ _ _ _ _ _; If one street lamp on the road is broken and other lights can work normally, then it is judged that the street lamp is connected by _ _ _ _.

18. Physics stipulates that the direction of _ _ _ _ _ _ _ directional motion is the direction of current, and the direction of current in copper conductor is the direction of free charge _ _ _ _ _ _ _.

19. When measuring current with an ammeter, first find out the range and minimum scale value of the ammeter, then turn on the circuit, and carefully observe whether the pointer is in _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Four. Application (***2 1)

20. Drawing questions (8 points)

(1) As shown in Figure A below, a beam of light is obliquely incident on the plane mirror, so as to draw the reflected light as much as possible.

(2) As shown in Figure B below, please draw the refracted light of incident light passing through the convex lens.

(3) As shown in Figure C below, according to the imaging characteristics of the plane mirror, draw the image of the object AB in the plane mirror.

(4) As shown in Figure D below, the vertex angle of the right-angle prism is 30, and a beam of light is vertically incident on the AB side, and then enters the air from the AC side. Please draw the light from the AC side.

2 1.(2 points) The following figure is the speed table of some media listed in the textbook.

What laws can you sum up from the above table:

( 1)________________________________________________________________;

(2)________________________________________________________________;

22.(2 points) When drumming, the scraps of paper scattered on the drum surface will jump, and the bigger the drum sound, the higher the jump; When the sounding tuning fork touches the water surface, it can splash, and the louder the sound of the tuning fork, the greater the splash; When the speaker sounds, the paper basin will vibrate, and the louder the sound, the greater the vibration. According to the above phenomenon, it can be summarized as follows:

( 1)_________________________________________________________________;

(2)_________________________________________________________________;

23.(4 points) After a piece of metal is frozen in the refrigerator, it will stick to your hands when picked up, as if there is a layer of glue on the surface of the metal. Please explain why? Take it out and put it for a while, and you can find that the metal block is wet. If you dry it with a towel at once, you will find it will get wet. Why?

24.(3 points) If the figure on the right is the melting curve of a crystal, the melting point of the crystal is _ _ _ _ _ _℃, while _ _ _ _ _ _ _ _ (fill in "AB", "BC" and "CD" in the figure) is in solid-liquid * * *, and it is _ _ when the crystal melts.

25.(2 points) At the gas station: People sometimes see such an eye-catching slogan: "It is forbidden to transport gasoline in plastic barrels". Please explain the reason for this slogan.

Five, experiment and inquiry (***22 points)

26.(7 points) Inquiry: What factors may be related to the size of convex lens imaging?

(1) Xiaoming knows that a magnifying glass is a convex lens through his previous study of physical knowledge. In the activity class, he observed his finger with a magnifying glass (as shown on the right) and saw the image of _ _ _ _ _ _ _ _ _ _ _. Then use it to observe distant houses and see _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

(2) Xiao Ming wants to know "What factors may be related to the size of convex lens imaging?" Please help Xiao Ming finish his guess. The size of convex lens imaging may be related to _ _ _ _ _ _ _ _ _ _ _ _ _.

(3) On the optical experimental platform, Xiaoming constantly changed the distance between the candle and the lens and moved the optical screen to carry out the experiment. The experimental data obtained are shown in the following table. According to the analysis data, the shorter the distance between the object and the convex lens, the larger the image on the optical screen is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

Distance from object to convex lens /cm 40 30 20 15 10 8

Distance from the image on the screen to the convex lens /cm 13.5 15 20 30 There is no image on the screen.

The size of the image on the screen is reduced, reduced and enlarged.

(4) When Xiao Ming took photos of graduation photo, the photographer found that there were still students on both sides who were not in the frame. At this time, the photographer wants the camera _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

27.( 10) The picture on the right shows an experimental device for students to observe the boiling of water.

(1) If you want to shorten the experiment time appropriately, you can adopt the following methods:

_______________________________;

_______________________________;

(2) In the process of observing the boiling of water, this classmate observed two situations before boiling and during the rising of bubbles in water during boiling, as shown in the right picture, and the picture _ _ _ _ is before boiling of water.

(3) When the water temperature rises to 90 degrees Celsius, record the water temperature every 65438 0 minutes to get the data in the table below. According to the data analysis, it can be concluded that the boiling temperature of water is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

(4) Please draw an image of "temperature-time" relationship on the following grid paper according to the data in the table below.

(5) According to the observed phenomenon, students analyze the data and draw the following conclusions:

(1) boiling is a phenomenon in which both the surface and the interior of a liquid are strongly vaporized at the same time.

② In the first 4 minutes, the water absorbs heat and the temperature rises;

(3) It can also be concluded that:

_____________________________________

_____________________________________

(6) If the heating is stopped after the water boils, the water _ _ _ _ _ (optional "can" or "can't") will continue to boil. According to the above experimental phenomena, the conditions for water boiling are: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

28.(5 points) The circuit of Xiao Ming's current measurement experiment with an ammeter is shown in the figure.

(1) Please draw lines instead of wires to connect the physical circuit diagram. The light bulbs L 1 and L2 are required to be connected in parallel, and the lamps L 1 and L2 are controlled by switching S 1 and S2 respectively, and the current through the lamp L 1 is measured by an ammeter.

(2) In order to study the current relationship in parallel circuits, he should continue to measure the current passing through _ _ _ _ _ _ _ _ _ _ _ _ _.

(3) In the experiment, a classmate just turned on the switch and found that the pointer of the ammeter turned to the far left, so he immediately turned off the switch. Would you please help him analyze the reason?

Reference Answers and Grading Criteria of Physics Final Examination Paper in Grade Eight

1. Choose (choose the only correct answer for each question, 3 points for each small question, * * 30 points. Don't choose, multiple choice and wrong choice are 0 points).

1.c； 2.b； 3.d； 4.a； 5.a； 6.c； 7.b； 8.a； 9.b； 10.d；

2. Selection explanation (2 points for choosing the only correct answer for each question, 3 points for explaining the reason, 5 points for each small question, *** 10, 0 points for not choosing, choosing more than one and choosing wrongly).

1 1.c； (2 points) Reason: It is said that water vapor in the air condenses into small water droplets and adheres to flowers and plants, which is a liquefaction phenomenon, and you can get 3 points. Students can also get extra points if they can tell other reasons for the wrong answer. )

12.d； (2 points) Reason: According to the characteristics of convex lens imaging, when the object distance is greater than the focal length, it becomes an inverted image. When the object distance is less than the focal length, it becomes an upright virtual image, and you will get 3 points. Students can score according to the characteristics of convex lens imaging and exclude other answers. )

Three. Fill in the blanks (each blank 1, *** 17)

13. Thermal expansion and cold contraction; 37.8; 0. 1;

14. Vaporization; Reduce;

15. Various;

16. Myopia; Concave lens;

17. and; String; And;

18. Positive charge; Conversely;

19. Zero score line; 0.02A0.46A

Fourth, application

20.( 1) * * 2 points, draw the line correctly 1 minute, and draw the reflected light correctly 1 minute;

(2)*** Draw 2 points of refracted light correctly, 1 minute;

(3)***2 points can correctly draw the image of AB in the plane mirror according to the imaging characteristics of the plane mirror, 2 points (including: equal distance, equal distance, object image line perpendicular to the mirror, virtual image 0.5 points each).

(4)* * * 2 The score of correctly drawing the normal is 1, and the score of correctly drawing the refracted light is1;

2 1.* * * 2 points. Get 1 point for each correct answer.

① Sound propagates fastest in solid, followed by liquid and gas;

② The speed of sound propagation in air is related to temperature. The higher the temperature, the faster the sound travels.

22.* * * 2 points for each correct answer, 1 point.

(1) Vibration produces sound;

② The greater the vibration amplitude of the object, the greater the loudness of the sound;

23.* * * 4 points.

It can be said that the metal will stick to the hand after being frozen because the water on the hand will freeze when it is cold, and you can get 2 points; It can be said that the reason for wiping is that the water vapor in the air liquefies into small water droplets when it meets the cold metal block and adheres to the fast surface of the metal. Two points.

24.70; BC; Suck; (65438+ 0 points per grid ***3 points)

25. Because gasoline will be charged due to friction when it shakes in the plastic bucket, the generated charge will accumulate on the oil bucket, and when it accumulates to a certain extent, it will discharge, which will easily ignite the gasoline and cause a fire. Therefore, it is forbidden to transport gasoline in the plastic bucket. 2 o'clock can basically explain.

Experiment and Exploration of verb (abbreviation of verb)

26.* * * 7 points

(1) becomes larger; Shrinking; (65438+ 0 point per grid)

② The distance between the object and the convex lens (1)

③ large; Far (per space 1 dot)

4 stay away; Shorten; (65438+ 0 point per grid)

27.* * * 10 point

① Cover the beaker; Switch to an alcohol lamp with a bigger flame; Heat with an external flame such as an alcohol lamp. (If you can speak a little, you will get 1 point, and if you leave two spaces, you will get 2 points * * *).

②B； ( 1)

③98; Less than; (65438+ 0 point per grid)

(4) Make the image correct by 2 points;

(5) when reaching the boiling point, continue to heat, but the temperature remains the same; ( 1)

6 no; The boiling condition should absorb heat continuously and the temperature should reach the boiling point of water; (65438+ 0 point per grid)

28.* * * 5 points

(1) 2 points will be deducted for correct circuit connection, and 0.5 point will be deducted for each wrong connection until the end;

②L2 bulb current; Total current of main roads; (65438+ 0 point per grid)

③ The positive and negative poles of ammeter are reversed; ( 1)