1. "People walk on the bridge, but the bridge water does not flow." The poet thinks that the reference for the choice of "bridge flow" is
A. Bridge B. Water C. River bank D. Soil
2. The following phenomena can be explained by the viewpoint of "random motion of molecules"
A. In spring, catkins fly. B. in summer, magnolia flowers smell fragrant.
C. In autumn, the leaves are falling. D. In winter, snowflakes are fluttering.
3. After the food is put into the refrigerator, the temperature decreases, and the change of its internal energy and its change mode are as follows.
A. Reduction and heat transfer B. Reduction and work
C. Increase and heat transfer D. Increase and do work
The highest temperature that can be measured by alcohol thermometer and kerosene thermometer is different, mainly because of the difference between alcohol and kerosene.
A. different boiling point B. different freezing point C. different specific heat capacity D. different density
5. When analyzing the connection relationship of various electrical appliances in complex circuits, the ammeter and voltmeter in the circuits can be simplified. The following treatment methods are correct
A. imagine the ammeter as an open circuit. Think of an ammeter as a large resistor.
C. Think of the voltmeter as an open circuit. D. Think of the voltmeter as a wire.
6. All the continents on the earth are floating on dense substances underground. The relationship between buoyancy f and gravity g of these continents is as follows
A.F & gtg B F & lt； Not sure.
7. Wenchang Middle School students told a miracle of life: during the earthquake, a man fell into a suddenly cracked ground fissure, and everyone around him thought he was killed. Unexpectedly, he was safely washed to the ground by a huge airflow from a depth of about100 m. Estimate the work that the airflow did to him during the ascent.
a . 6× 102j b . 6× 103j c . 6× 104j d . 6× 105j
8. In figure 1, the image of candle flame observed by people through convex lens is
A. the light screen can accept the real image.
B. the real image is not acceptable by a light screen.
C. virtual image can be accepted by the light curtain.
D. virtual image, which cannot be accepted by the light screen.
9. Figure 2 shows the contour map of a high mountain. When a mountaineer arrives at point B from point A, the following statement is correct.
A. Weight gain of athletes
B. the athletes' gravitational potential energy increases.
C. Increased atmospheric pressure faced by athletes
D the distance traveled by athletes is1000m.
10. When the field survival training class marched in a hurry at night, Xiao Wang led everyone to advance against the moonlight. Somewhere, they avoided the "dark ground" and chose the "bright ground", and the students who ran in front fell into the puddle one after another. The reason for the "bright future" is
A. diffuse reflection of light on the ground B. specular reflection of light on the ground
C. diffuse reflection of light on water D. specular reflection of light on water
1 1.LED light source is widely used because of its advantages of energy saving, environmental protection and safety. For example, every word behind a company signboard is made up of many LED light strings. When Master Wang disconnects a place when debugging the circuit, the second word on the signboard goes out immediately, and all other words glow normally (as shown in Figure 3). According to this phenomenon, it is judged that the connection mode between the light strings behind the luminous characters is correct.
A. this word must be connected with other words.
This word must be juxtaposed with other words.
C. the strokes of this word must be connected.
D. the strokes of this word must be parallel.
12. As shown in Figure 4, the power supply voltage is constant. When the switch S is closed and the slider P of the sliding rheostat moves downward.
A. current means decrease and voltage means increase.
B, current means decrease, and voltage means decrease.
C. current means increase and voltage means decrease.
D. current means increase, and voltage means increase.
Fill in the blanks (this big question 12 small questions, 2 points for each small question, ***24 points)
13. As shown in Figure 5, it is a sand truck on the beach around the island road. Its tires are wide and big, in order to reduce the _ _ _ _ _ _ of the vehicle on the ground, and the pattern on the tire surface is for _ _ _ _ _ _ _.
14. Gas lighters used in daily life involve some thermal knowledge, such as pressurizing combustible gas and loading it into the machine; In the process of ignition, the pressure of combustible liquid is reduced after it is ejected, and it soon becomes gas. (Fill in the name of the change of material state)
15. In March 2009, a fire broke out in a Dojo in Nantou County, Taiwan Province Province, and it was found that the fire source was a "crystal ball". In order to avoid disaster, a crystal ball was placed at the entrance of the Dojo. As shown in Figure 6, the crystal ball has a _ _ _ _ _ effect on light (optional "convergence" or "divergence"), which makes the plastic carpet under the crystal ball increase and cause a fire.
16. An electronic tile is marked with the words "220 V 1 10 W", and the current passing through it during normal operation is _ _ _ _ _ A；; If it works normally for 2 h, the power consumption is _ _ _ _ _ _ _ _ J.
17. The propagation speed of electromagnetic waves in the air is about m/s, the frequency of electromagnetic waves emitted by Xiamen News Broadcasting FM Station is 99.6 MHz, and the wavelength of electromagnetic waves is m (only integers are reserved in the calculation results).
18. As shown in Figure 7, brush a thin plastic sheet on the teeth of combs with different densities at the same speed, and hear different sounds, which can verify that the _ _ _ _ _ _ _ _ _ _ _ _ of the sound is related to the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.
19. As shown in Figure 8, if A and C are terminated on the circuit, when the slider P moves to the left, the resistance value of the rheostat connected on the circuit is _ _ _ _ _ _ _ _ _; If only _ _ _ _ _ _ _ two terminals are connected, it is equivalent to connecting a constant resistance on the circuit.
20. Install springs on the insoles of advanced running shoes. When the runner's feet land, the spring is compressed and _ _ _ _ _ _ _ can be increased; When the foot leaves the ground, this part of energy is converted into his _ _ _ _ _ energy, which makes him run more briskly.
2 1. As shown in Figure 9, the table tennis ball will be suspended in the funnel by blowing downward from the inverted funnel opening A. Explain the gas velocity _ _ _ _ _ and gas pressure _ _ _ above the table tennis ball when blowing. (Select "Larger" or "Smaller")
22. The "heart" of the electric bicycle is the motor. Its working principle is that when the power is cut off, the motor becomes a "generator" and realizes "self-power generation". Its power generation principle is as follows.
23. Figure 10 shows a liquid pressure gauge. The same pressure gauge is used to measure the pressure of different liquids at the same depth. The greater the density of the measured liquid, the greater the height difference between the left and right liquid levels of the U-shaped tube. Use different pressures to measure the same pressure. The greater the density of the liquid in the U-shaped tube, the greater the height difference between the left and right liquid levels.
24.a and B are two metal balls with the same material. A has a mass of 8 1 g and a volume of 30 cm3, while B has a mass of 50 g and a volume of 25 cm3. If one of the balls is solid, the solid ball should be _ _ (choose "A" or "B"), and the density of this metal is _ _ _ _ _ _ g/cm3.
III. Short answer questions (this big question 1 small question, ***4 points)
Skateboarding has become a very popular fashion sport for teenagers. Skateboarding enthusiasts can stand on a skateboard with a rough surface and push back with one foot to accelerate their progress; When his feet stand on the skateboard, he can still slide freely on the horizontal ground, as shown in figure 1 1.
Please describe two scenes related to physics in the table below according to the above graphic information, and write down the physical knowledge involved.
Physical knowledge of landscape
One example is that there are wheels under the skateboard, and rolling instead of sliding can reduce friction.
1
2
Four, drawing questions (this big question 3 small questions, each small question 2 points, ***6 points)
26. A water strider stops on the water, as shown in figure 12. Please draw a schematic diagram of gravity G and the force F of water on the water strider at point O..
27. As shown in figure 13, please draw a general diagram of the light path of light AB from air to glass, and then from glass to air.
28. Figure 14 is the design principle diagram of the repulsive maglev train. A is an electromagnet installed on the track, and B is a solenoid installed on the car body. The current direction is shown in the figure. Please mark the N pole of energized solenoid B and the N pole of electromagnet A respectively in the drawing.
Five, experiment and inquiry questions (this big question 3 small questions, ***22 points)
29.(6 points) As shown in Figure 15, in order to explore the factors affecting the thermal expansion of solids, a scientific and technological team conducted relevant experiments with aluminum bars, and the experimental data are as follows:
(1) By analyzing the experimental data of experimental serial numbers 1, 2 and 3, we can get the relationship between the elongation of aluminum bars and their _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
(2) In order to explore the relationship between the elongation of aluminum bars and the temperature rise, three groups of experimental data with experimental serial number of _ _ _ _ _ _ _ should be selected for analysis;
(3) According to your analysis conclusion, you can calculate the elongation of Experiment 6 △ L = _ _ _ _ _ mm
30.(8 points) Xiaoming used the pulley block as shown in figure 16A in the experiment of "measuring the mechanical efficiency of pulley block". The experimental data are as follows:
(1) According to the analysis of the data in the table, the mechanical efficiency of the pulley block is related to the rising height of the object and the gravity of the lifted object. (Select "relevant" or "irrelevant")
(2) Please write the expression η = _ _ _ _ _ _ _ _ with the symbols of the physical quantities measured in the experiment, and calculate the mechanical efficiency of the fourth experiment as _ _ _ _ _ _ _ _ _ _ _;
(3) If the device shown in Figure 16B is used to carry out the experiment and lift the same weight to the same height, more extra work is needed, so the mechanical efficiency is more _ _ _ _ _ _ _ _ _ _ _ _ _ _ _;
(4) About the mechanical efficiency when lifting heavy objects with the same pulley block, the following statement is correct ().
A. The heavier the lifting object, the greater the mechanical efficiency. The greater the useful work, the higher the mechanical efficiency.
C. the greater the extra work, the less the mechanical efficiency. D the mechanical efficiency of the same machine is constant.
3 1.(8 points) As shown in figure 17, it is a circuit diagram for measuring the electric power of small bulbs. The rated voltage of the small bulb is 2.5 V, and the resistance is about10 Ω. The ammeter has two ranges of 0 ~ 0.6A and 0 ~ 3A, and the voltmeter has two ranges of 0 ~ 3 V and 0 ~ 15V.
(1) In this experiment, the measuring range of the ammeter should be _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
(2) Xiaodong correctly connects the circuit. After closing the switch, no matter how to adjust the sliding rheostat, the light bulb does not light up. After investigation, the ammeter and voltmeter are all fault-free. Xiaodong guessed that it might be:
A. the filament is broken. B. the small bulb is short-circuited and C. the rheostat is open.
Which guess is correct? Xiaodong listed several possible situations of electrical representation, as shown in the following table. Please decide which guess is correct in each case and fill in its serial number in the corresponding space.
(3) After Xiaodong eliminated the fault, the curve of the current passing through the small light bulb changing with the voltage was measured through experiments, as shown in figure 18. As can be seen from the figure, when the voltage across the small bulb is 1.5 V, its resistance is _ _ _ Ω; By adjusting the sliding rheostat, the bulb can emit light normally, and its rated power is _ _ _ _ _ _ W；;
(4) What conclusion can you draw by analyzing this curve carefully? _______________________________ 。
Six, calculation problem (this big problem 3 small questions, ***20 points)
32.(6 points) Xiamen-Tianjin route plays an important role in strengthening exchanges between Fujian and Taiwan and promoting the construction of Haixi. The newly opened Xiamen-Jinjin Second Waterway takes only 24 minutes to sail, and the length of the waterway 18 km is only half of that of the first waterway. Q:
(1) What is the average speed of passenger ships sailing in the second channel?
(2) If the average speed of express flights in the first channel is 50 km/h, how much navigation time can be saved by choosing the second channel than choosing the first channel?
33.(6 points) There are two resistors, r1= 2Ω, R2 = 8ω. When they are connected in series at the two poles of the power supply, the current of the circuit is 0.4A If these two resistors are connected in parallel at the same power supply, find the total current of the circuit at this time and the electric power of R2.
34.(8 points) When the resistance of a metal is at t≥0℃, the relationship between the resistance Rt and the temperature T is RT =100 (1+5×10-3t) ω. Using this characteristic, a metal resistance thermometer can be made. Its schematic diagram is shown in figure 19. The voltage of the power supply is constant at 3 v. The metal resistor Rt is used as the temperature measuring probe of the thermometer. After standing at 0℃ for a period of time, close the switch and adjust the sliding rheostat R0 to make the current indicator just reach full scale 15 mA.
(1) Find the resistance of R0 access circuit;
(2) What is the temperature scale value corresponding to the center of ammeter dial?
(3) If voltmeter is used instead of ammeter, the voltage representation will increase with the increase of probe temperature. Please draw the circuit diagram you designed.
Xiamen graduated from junior high school in 2009 and took the entrance examination for senior high school.
Physical reference answers and grading standards
First, multiple-choice questions (this big question * * 12 small questions, 2 points for each small question, 24 points for * * *)
The title is123455678911112.
The answers are bb, aa, cc, cc, bb, bb.
Second, fill in the blanks (this big question * * 12 small question, 1 point per grid, ***24 points)
13. Pressure increase 14. Liquefaction and vaporization 15. Convergence; gather
16.0.5 7.92×10517.3×108 318. Tone (high and low) frequency (fast and slow)
19. Little A, B 20. Elastic potential energy (energy) Dynamic potential energy (energy) 2 1. Smaller and smaller.
22. The electrified coil (conductor) is electromagnetically induced by the force in the magnetic field.
23. Size 24. Answer 2.7
III. Short answer questions (this topic is entitled 1 small question, and 25 is entitled 4 points)
25.
Landscape (65438+ 0 each) Physical knowledge (65438+ 0 each)
1 the roughness of the upper surface of the skateboard, the rougher the contact surface, the greater the friction.
When one foot pushes backward, the force of skateboarding accelerating forward is mutual.
Force can change the motion state of an object.
When you don't pedal, you can still slide freely on the horizontal plane. All objects have inertia.
Skateboarders bend forward to slide, lower their center of gravity and improve their stability.
Four, drawing questions (this big question ***3 small questions, each small question 2 points, ***6 points)
26.(2 points) 27. (2 points) 28. (2 points)
Five, experiment and inquiry questions (this big question ***3 small questions, ***22 points)
29.(6 points) 2 points for each small question.
(1) Original length (2) 1, 4,5 (3) 2
30.(8 points) 2 points for each small question
(1) irrelevant (2)
Big (multi) small (low) a
3 1.(8 points) 2 points for each small question.
(1) 0~0.6-0 ~ 3v (2)
(3) 6 0.75
(4) The resistance of small bulbs increases with the increase of temperature (voltage and current).
(If there are other reasonable answers, the same points will be given) Is this correct? There is no calculation problem.