Note: This paper consists of 8 pages. 100. Examination time 100 minutes.
1. Fill in the blanks (this big question * * 10 small question, 2 points for each small question, 20 points for * * *)
1. In class, the teacher's voice is introduced to the students through _ _ _ _ _ _ _ _ _; The ringing sound can splash when it touches the water surface, indicating that the sound is emitted by the _ _ _ _ _ _ _ _ of the object.
2. The "hand shadow" made under the light is the _ _ _ _ _ _ _ phenomenon of light; The glass lens of myopia glasses is equivalent to _ _ _ _ _ _ _ _ lens.
3. "Nanometer" (nm) is the unit of _ _ _ _ _ _ _; One of the characteristics of nano-M materials is _ _ _ _ _ _ _ _ _ _ _.
There is a folk proverb in our country called "it is cold before frost and cold after snow." Frost is caused by the phenomenon of _ _ _ _ _ in the air when the temperature is low; When snow melts, it needs _ _ _ _ _ _ heat.
Xiaoming accompanied his father to the park for a walk. He saw the reflection of willow branches swaying from side to side in the lake. Then the "reflection" is relatively moving and relatively static.
6. As shown in the figure, the small magnetic needle can rotate freely on the paper. After closing the switch, the upper end of the energized solenoid is N pole, so the small magnetic needle will rotate in the direction of _ _ _ _ _ _ _ _. When the slider of the sliding rheostat moves to the B end, the magnetism of the energized solenoid will be _ _ _ _ _ _ _ _ _ _ _.
7. As shown in the figure, put the experimental "small table" into the sand table and observe the depth of sinking into the sand table. Comparing the situation in Figure A and Figure B, it can be seen that the effect of pressure action is related to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _; Comparing Figure B and Figure C, we can see that the effect of pressure action is related to _ _ _ _ _ _ _ _ _ _ _.
8. As shown in the figure, A and B are two cylindrical containers with different heights. The ratio of bottom area inside the containers is 2: 1, and both containers are filled with water. Now put the wood blocks A and B with the mass ratio of 1: 3 into two containers respectively, and the pressure ratio of water to the bottom of the container is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
9. When the current in the human body exceeds 30mA, it will be life-threatening. If someone's body resistance is 1 100ω, then his safe voltage _ _ _ _ _ _ _ _ _ V；; How will safe voltage change in the wet rainy season? _______________________________________.
10. Diesel engine is a common heat engine in industrial and agricultural production. It is known that the efficiency of a certain type of diesel engine is η, and the calorific value of diesel oil is Q. When a diesel engine with a mass of m is completely burned, the heat it can release is Q = _ _ _ _ _ _ _ _ _ _ _ _ _ _ _, and the useful work done by the diesel engine transformation is W = _ _ _ _ _ _ _ _ _.
Second, multiple-choice questions (this big question * * 13 small questions, 2 points for each small question, ***26 points)
Note: in 1 1 ~ 20 questions, only one option is correct.
Noise control is one of the main projects of urban environmental protection. Which of the following measures cannot reduce noise? [ ]
A. it is forbidden for motor vehicles to whistle in urban areas. Reduce the emission of carbon dioxide gas.
C. install a muffler on the automobile exhaust pipe. D plant a variety of grass and trees on both sides of urban streets and open spaces.
12. In daily life, people all know that liquids are difficult to be compressed. This is because []
A. attractive between molecules. B. there are gaps between molecules. C. molecules are constantly moving. There is repulsion between molecules.
13. During the power stroke of the internal combustion engine, the high-temperature gas expands rapidly to do work, and the temperature and internal energy of the gas change to [].
A. the lower the temperature, the lower the internal energy. When the temperature is constant, the internal energy is constant. C. the higher the temperature, the higher the internal energy. D. the lower the temperature, the higher the internal energy.
14. For electromagnetic waves propagating in the air, the following statement is true []
A. the lower the frequency, the greater the wave velocity. B. The lower the frequency, the longer the wavelength. The longer the wavelength, the greater the wave velocity. D. the wavelengths of electromagnetic waves are all the same.
15. The two forces acting on an object are F 1 = 3n and F2=5N respectively, and these two forces are on the same straight line, then the resultant force of F 1 and F2 [].
A. it must be 8N B. it must be 2N C. it may be 3N or 5N D. it may be 2N or 8N.
16. The following table shows the freezing and boiling points of some substances. According to the table below, the thermometer that can measure the temperature in various regions of China is []
A. Alcohol thermometer B. Ether thermometer C. Water thermometer D. Mercury thermometer
17. At the Sydney Olympic Games on September 22nd, 2000, China athlete ding meiyuan won the gold medal in women's weightlifting over 75kg, with a clean and jerk performance of165kg. It is estimated that the work she did on the barbell during the whole clean and jerk is []
a . 3× 102j b . 1× 103j c . 3× 103j d . 5× 103j
18. As shown in the figure, a magnet is fixed on a trolley placed on a smooth horizontal surface, and a magnet is hung by a wooden pole, and a certain gap is always maintained between the two magnets. The state of the car is []
A. move left, faster and faster. B. move right, faster and faster.
C. Uniform linear motion or static D. Sometimes fast and sometimes slow linear motion
19. In the corridors of residential buildings, only occasional people pass by at night, and the corridor lights are always on, which will cause great waste. Researchers use "photosensitive" materials to make "light-controlled switches", which automatically turn off at dark and turn on at dawn; The "voice-activated switch" made of "sound-sensitive" material is used to automatically turn off when someone makes noise when walking, and automatically turn on when nobody walks. As shown in Figure 5, in the circuit, [] belongs to the corridor lamp circuit.
20. The physics teacher prepared some white sugar water in a rectangular glass jar in some way in the laboratory. Two days later, the students came to the laboratory for class. A student used a laser pen to shoot light obliquely upward into the white sugar water from the outside of the glass jar, and found a strange phenomenon: the light path in the white sugar water is not a straight line, but a downward curved curve, as shown in the figure. Regarding the explanation of this phenomenon, the students put forward the following conjectures, among which the conjecture that can reasonably explain this phenomenon is []
A. Refraction of the glass jar B. The light emitted by the laser pen is absolutely parallel.
C. The density of white sugar water is uneven, and the deeper it is, the greater the density is. D. the light of various colors emitted by the laser pen is dispersed.
Note: in 2 1 ~ 23 questions, at least two options are correct in each question.
2 1. Regarding optical equipment or equipment, the following statement is true []
A. The lens of a camera and a slide projector is equivalent to a convex lens.
When using a slide projector, slides should be placed upside down in order to get an upright image on the screen.
C. a magnifying glass can only enlarge.
D. "Presbyopia" is the image behind the retina.
22. Regarding the safe use of electricity, the following statement is true []
A. You won't get an electric shock as long as you stand on an insulated wooden bench to fix the lamp. B. the high-voltage line should be grounded, so don't approach it.
C. If someone gets an electric shock, you should pull the person away first. D when the lighting circuit is connected, the switch should be connected to the live wire.
23. Two identical balls A and B are thrown vertically upwards and downwards at the same speed on the same horizontal plane, and the two balls bounce repeatedly on the ground. Air resistance is not included in the movement, and energy loss is not included in the collision with the ground. Then the following statement is correct []
A. When the ball falls in the air, the gravitational potential energy decreases and the kinetic energy increases. B. at the moment of throwing, the kinetic energy of ball a is greater than that of ball B.
C at any moment, the mechanical energy of two balls is equal. D. the maximum gravitational potential energy of ball a is greater than that of ball B.
Three, drawing questions (this big topic ***2 small questions, each small question 3 points, ***6 points)
24. As shown in Figure A, the refracted light passes through the optical center; In figure b, the refracted light is parallel to the main optical axis; The point S' in figure C is the image of the point light source S. Please draw the incident light in figures A and B and the reflected light in figure C. ..
25. Connect the objects in the picture to meet the requirements of measuring resistance by voltammetry.
Fourth, the calculation problem (this big problem * * 3 small problems, *** 16 points)
26.(4 points) A solar water heater is filled with 80kg of water, the solar energy absorbed by the collector tube per minute is about 7× 104J, and the specific heat capacity of water is 4.2× 103J/(kg? ℃)。 How many degrees Celsius can the water heater raise the water temperature per hour?
27.(6 points) The crane used in the construction site is as shown in the figure. 0B length 15m, 0C length 25m. There is a movable pulley block on section 0C, and a counterweight at end A.. G is 10N/kg regardless of the gravity and friction of the pulley block. When the pulley block is at point B, the maximum weight of the weight that can be safely lifted is 800kg.
(1) When the pulley block moves to point C, seek the maximum mass of the weight that can be safely lifted.
(2) It takes 8m for the crane to lift 800kg weight at a uniform speed 10s. Find the power of wire rope tension on pulley block.
28.(6 points) The simplified circuit of the incubator is shown in the figure. A is a temperature sensor, which acts as a switch and automatically disconnects the circuit when it reaches the set temperature; When the temperature is lower than the set temperature, the circuit is automatically connected. S is the temperature setting switch of the incubator, which has three grades, namely 60℃, 50℃ and 40℃, and the heating power is 90W, 72W and 45W respectively. The power supply voltage is 36V, and R 1, R2 and R3 are all heating elements.
(1) When S is set to 1, what is the heating power? What is the resistance of R 1?
(2) When S is set to position 3, what is the current in the circuit?
(3) When S is set to position 2, what is the resistance of R2?
Five, short answer questions (this topic ***2 small questions, each small question 3 points, ***6 points)
29. The picture shows the photo of the driver while driving.
(1) Why is the steering wheel surface rough? Please explain briefly.
(2) According to the photo, ask another physical question and explain it briefly.
30. In order to determine the wind direction, you can immerse your arm in the water and then lift it up. From which side of your arm does the wind blow? It feels cold.
(1) Explain the above phenomenon briefly with the physical knowledge you have learned.
(2) Give an actual example with the same principle as the above phenomenon.
Six, comprehensive questions (this big question * * 5 small questions, ***26 points)
3 1.(5 points) The picture shows part of the operation of the experiment to explore what factors are related to the size of buoyancy. According to this picture, answer the following questions:
(1) If the relationship between buoyancy and immersion depth is explored, the operation to be selected is _ _ _ _ _ _ _ (fill in the serial number).
(2) If the selected operation is 246, we can discuss the relationship between buoyancy and _ _ _ _ _ _ _.
(3) If we explore the relationship between buoyancy and the volume of perspiration liquid, the operation we should choose is _ _ _ _ _ _ _ (fill in the serial number).
32.(5 points) In the experiment of "measuring the electric power of small light bulb", it is known that the rated voltage of small light bulb is 25V, and the power supply is two dry batteries, and the equipment is in good condition.
(1) A classmate connected the circuit. After connecting the last wire, he saw that the light bulb was shining, his eyes were brighter than usual, and the deflection angle of the voltmeter pointer became smaller. Then in the process of connecting the circuit, what does not meet the requirements is:
①_______________________________________________;
②_______________________________________________;
③_______________________________________________.
(2) After the circuit is correctly connected, close the switch and adjust the slider of the sliding rheostat. When _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _, the rated power of the small light bulb is _ _ _ _ _ _ _ _ _ W.
33.(5 points) A classmate used a "Coke bottle" to do pinhole imaging experiment, and the experimental device is shown in Figure (a).
(1) Please draw the image A' c' of candle AB on the translucent paper in Figure A. 。
(2) The classmate found that after the candle and the hole are fixed, the farther away from the hole, the bigger the image. He measured the height of the image at different distances (see the table below). Please draw an image of the relationship between H and S in the coordinates of Figure B according to the data in the table.
(3) What is the relationship between H and S from the image?
34.(6 points) The main component of pencil lead is graphite. Pencils with different hardness have different uses, such as 6B soft pencil for drawing, HB pencil for writing and 6H hard pencil for drawing. Pencil lead is a conductor, so what is the relationship between the resistance and hardness of pencil lead? Please design an experimental scheme to explore this problem.
(1) Write down the main experimental steps and the physical quantities to be measured (in letters).
(2) Analyze the measured physical quantities and explain the corresponding relationship between pencil lead resistance and pencil lead hardness.
35.(5 points) In order to measure the sliding friction of wood blocks, the two experimental groups designed two experimental schemes, A and B, respectively, and the experimental devices are shown in the figure. The gravity of the spring dynamometer is not considered in the experiment.
Scheme A: Pull the wooden board with iron wire on the horizontal experimental desktop, and pull the wooden block horizontally along the direction of the wooden board with spring dynamometer to make the wooden block slide on the wooden board.
Scheme B: Put the wooden board on the horizontal experimental platform, pull the wooden block horizontally with iron wire through the spring dynamometer, and pull the wooden board horizontally along the direction of the wooden board to make the wooden board slide under the wooden block.
(1) Considering the experimental operation, the _ _ _ _ _ _ _ _ scheme should be selected. Briefly describe the reasons for your choice?
(2) Considering the experimental error, _ _ _ _ _ _ scheme should be selected. Briefly describe the reasons for your choice?