Hebei province in early 2006, the comprehensive examination paper of science in the middle school entrance examination (experimental area of curriculum reform)
First, multiple-choice questions (2 points per question)
1. A classmate analyzed some practices in life. What do you think is unreasonable?
A. When the glass tube is connected to the rubber tube, first wet the glass nozzle with water, which will play a lubricating role.
B. Weightlifters apply "magnesium powder" on their hands before the competition in order to reduce friction.
On rainy days, motor vehicles should drive at a low speed because the friction between the wheels and the ground is very small.
D pencil powder is added to the rusty lock for lubrication.
2. The following instruments or tools in the process of use, using the lever principle of a group is
① Measuring cylinder ② Scissors ③ Beaker ④ Pipe clamp ⑤ Tray balance ⑤ Spring dynamometer
A.①②③ B.②④⑤
c.①③⑤ D.④⑤⑥
3. The following data is closest to reality.
A. The sprinter's100m speed is about 15m/sb. The diameter of table tennis is about 40 mm.
C. safe voltage to human body is not higher than 220 V D, and the weight of middle school students is about 50 N.
The following statement about "the speed of sound" is correct.
A. the propagation speed of echo is less than that of original sound.
B. Sound travels fastest in a vacuum.
C. the faster the object vibrates, the faster the sound propagates.
D. the propagation speed of sound has nothing to do with the amplitude of object vibration.
5. In the formation process of the following phenomena, one group that absorbs heat is
(1) in spring, ice and snow melt into streams; ② In summer, water pipes "sweat".
In autumn, dew condenses on the grass. In winter, frozen clothes will be dried.
A.①② B.②③ c.①④ D.③④
6. Xiao Ming keeps the position of convex lens unchanged when exploring the imaging law of convex lens. He placed the candle at four points, A, B, C and D, and adjusted the position of the light screen respectively, as shown in Figure 2. After exploration, he summed up the following statement. The correct answer is
A. the camera is made by using the imaging characteristics of the candle placed at point a.
B the magnifying glass is made by using the imaging characteristics of the candle placed at point B.
C. the slide projector is made by using the imaging characteristics of candles placed at point D.
D. the image of the candle at point b is bigger than that at point C.
7. In the high jump competition, the following statement is correct (excluding air resistance) from take-off to landing.
A. In the rising process, kinetic energy decreases and mechanical energy decreases.
B. In the rising process, the gravitational potential energy increases and the mechanical energy increases.
C. In the process of falling, the gravitational potential energy decreases and the mechanical energy remains unchanged.
D. In the process of falling, the gravitational potential energy decreases and the mechanical energy decreases.
8. Figure 3 is the schematic diagram of the automatic temperature alarm, which uses a lot of physical knowledge.
The following statement is incorrect.
A. Mercury in a thermometer is a conductor.
B. Thermometers work according to the characteristics that liquids expand when heated and contract when cooled.
The electromagnet in the alarm uses the thermal effect of current.
D. the electromagnetic relay is a circuit switch.
9. An object on a smooth horizontal plane is only affected by a pair of balancing forces in the horizontal direction, so the object
A. You can do uniform linear motion in any direction on the horizontal plane.
B.you can only do uniform linear motion at a certain speed.
C. it can only move in a straight line at a uniform speed in one force direction.
D it is either stationary or moving in a straight line at a constant speed along the direction of force.
10. As shown in Figure 4, the power supply voltage is U= 18V, and the rated voltage of the small bulb L is 9V. When the slider P of the sliding rheostat moves to the midpoint, the small bulb L emits light normally; When the slider P moves to the extreme right, the actual power of the small bulb L is 6W. The rated power of the small bulb and the maximum resistance of the sliding rheostat are respectively
a . 13.5 w 6ωb . 6w 13.5ω
c . 6w 12ωd . 13.5 w 12ω
II. Fill in the blanks (65438+ 0 point for each blank)
Axe is a common tool for carpenters. After a period of time, the carpenter will sharpen the axe to increase the pressure; In the process of grinding, the temperature of the axe keeps rising, and the mechanical energy is converted into. The axe was loose, and the carpenter slammed one end of the handle on the ground several times, and the axe was firmly set on the handle. This is because.
12. A cargo ship with a displacement of 1 000t is sailing at sea, and the buoyancy is n when it is fully loaded; After it sailed into the Yangtze River from the sea, the volume of the hull immersed in the water (choose "bigger", "smaller" or "unchanged"); Cargo ships from Shanghai to Chongqing have to pass through Gezhouba and Three Gorges Dam shiplocks, both of which are built according to the principle. (take g= 1 month)
13. For the circuit shown in Figure 5, after the switch S is closed, the indication of the ammeter (fill in "bigger", "smaller" or "unchanged"); If the current indicator changes by 0. 1A, the resistance r = ω. (Power supply voltage remains unchanged)
14. The new electric auxiliary solar water heater can start the electric heating tube to heat water in bad weather and low heat absorption power. Xiao Ming's family bought such a water heater, and the following table shows a set of main technical parameters on its nameplate (heat absorption power refers to the energy of solar radiation absorbed by the collector tube every second under the sunlight irradiation).
Volume /l lighting area of collector tube/m. heat absorption power /kw rated voltage, v rated power of electric heating tube /kw.
160 2 1~2 220 2
On a certain day in winter, the water heater is filled with 5℃ cold water, the average heat absorption power of the collector tube is 1250W, and the efficiency of the water heater is 56%. When the sun shines for 8 hours during the day, the heat absorbed by water is J, and the temperature reached is℃. Xiao Ming's family needs bath water above 45℃ at night, so the electric heating tube at least works normally.
C water = 4.2× 103 j/(kg? ℃)
15. On May 22nd, 2005, members of the China Mountaineering Survey Team successfully climbed the summit again and re-measured Mount Everest. Measure the atmospheric pressure gradually received by the team members when they climb upwards; The reason why the players want to cook rice in a pressure cooker is. In addition, the survey team members also need to carry oxygen cylinders. The purpose of these oxygen cylinders is that the team members often carry self-heating convenience foods to replenish energy when climbing mountains. The principle of heating is to use quicklime to react with water to release heat. The chemical equation of this reaction is.
Third, drawing and experiment questions (this big question ***6 small questions; 4 points for 16, 3 points for 17, 4 points for 18 and 6 points for 36 items)
16. Draw according to the following requirements.
(1) A shot with a weight of 40N rolls to the right on the ground. Please draw the gravity map of shot put in Figure 7.
(2) As shown in Figure 8, it is the light reflected from the water surface. Please draw the general directions of incident light and refracted light corresponding to human light in the picture.
17 Xiaoming got several sets of data when he did the experiment of "studying the pressure of liquid", as shown in the following table:
No. liquid depth/cm rubber film direction pressure Keiso liquid level height difference cm
1 water above 5 4.8
2 water 5 down 4.8
3 Water 5 faces the side 4.8
4 water 10 towards the city surface 9.5
5 water 15 facing the side 14.2
6 alcohol 15 facing the side 1 1.4
According to the data in the table, please answer the following questions:
(1) Comparing the three groups of data with serial numbers 1, 2 and 3, we can draw the following conclusions.
(2) Comparing three groups of data with serial numbers of 3, 4 and 5, we can draw the following conclusions.
(3) Comparing the two groups of data with serial numbers 5 and 6, we can draw the following conclusions.
18. When Xiao Ming measures the density of vegetable oil, he operates in the following order: ① Measure the mass of the empty beaker M 1 with a balance; ② Pour 8 portions of vegetable oil into the beaker, and measure the total mass m2 of the beaker and plants; (3) pour that vegetable oil in the beaker into a measuring cylinder, and measure the volume v of the vegetable oil; ④ Calculate the density ρ of vegetable oil.
(1) The following table is a record data table designed by Xiao Ming according to the above experimental operation. Please fill in the figures in the table according to Figure 9.
According to the completed form.
physical quantity
Mass of empty beaker m 1/g beaker and total mass of vegetable oil m2/g vegetable oil volume.
What is the density ρ/kg of V/cm3 vegetable oil? m-3
Measured value 15 20
(2) The density value obtained by Xiaoming according to the above experimental operation is greater than the true value of A. Please design an experimental scheme with small error on the basis of Xiaoming's experiment and write the final expression of juice burial density.
A small bulb with a melting voltage of 6V flows through about 0.3A during normal operation. Xiaoming wants to measure this small one.
The rated power of light bulbs, the laboratory has the following equipment:
One ammeter, one voltmeter, one switch, three sliding rheostats with specifications of "10Ω la", "50ωO5A" and "1kΩ ia", several wires and power supply (voltage: 12V).
(1) Xiaoming designed the circuit diagram as shown in figure 10. Through analysis, Xiao Ming thinks.
The sliding rheostat with the specification of-should be selected.
(2) Figure ii connects some circuits. Please follow the circuit diagram shown in figure 10, and use the stroke line instead of the wire to connect the circuit completely.
(3) Xiao Ming correctly selects the sliding rheostat, connects the circuit in Figure ll, closes the switch, and finds that the light of the bulb is dim and the ammeter has instructions. Move the slider of the sliding rheostat at will, and the voltage indication is constant (the indication is not zero) and less than 6V. The specific reason is that
(4) Xiao Ming continued the experiment after troubleshooting. When the voltmeter reads 6V, the ammeter (as shown in figure 12) reads -A, and the rated power of the small shower is W.
(5) Without changing the circuit connected above, the experiments that can be completed are as follows: (Write only one).
Fourth, the calculation problem (this big question ***3 small questions; /kloc-6 points for 0/9 and 7 points for 20 items. When answering, it is required to have the necessary text description, formula and calculation steps. , and only write the final grade without scoring)
19. Pulley is a simple machine that we often use in our daily life and production. Using pulleys can bring us many benefits.
(1) Please analyze the experiment in figure 14 and explain the characteristics of the pulley in the figure;
(2) When Xiao Ming experimented with the pulley block as shown in Figure 15, the object with the weight of 12N was lifted 10cm within 3s with a pulling force of F=5N. Q: What is the mechanical efficiency of the pulley block and what is the power of the pulling force F?
4l Xiaoming bought an electric oven with three heating powers: low, medium and high.
Fig. 16 is a simplified internal circuit diagram, and the switch S 1 can contact the contacts a and b respectively. It is known that r1= 48.4Ω, R2 = 96.8ω, and the power supply voltage remains unchanged. Please analyze and answer the following questions:
(1) When the switch S 1 is set to terminal B and S2 is closed, where is the electric oven? Briefly explain the reasons
(2) When the electric oven works in the middle position, what is the electric power consumed?
(3) When the electric oven works in a high-grade position, how much power does it consume to heat food for 6min?
Unified entrance examination for junior middle school students in Hebei Province in 2006
Reference answers and grading standards of comprehensive science examination questions
First, multiple-choice questions (this big topic ***23 small questions, 2 points for each small question, ***46 points)
The title is123455678911112.
Answer b c b d c c c d
Second, fill in the blanks and answer short questions (this big question is ***9 small questions; 65438 +0 points per grid, ***30 points)
1 1. Reduce the internal energy (or heat energy) in the stressed area. Axes have inertia.
12. 107 transformers and connectors
13. Larger 60
14.2.0 16× 107 35 3360
15. Reduce and increase the pressure of gas in the pot, and increase the boiling point of breathing liquid CaO+H2O = Ca(OH)2.
Scoring Note: The second blank only answers "Raise the boiling point" and gives the same score.
Third, drawing and experiment questions (this big question ***6 small questions; 4 points for question 33, 3 points for question 34, 4 points for question 35,
6 points for item 36, 37 and 38 1 point, ***27 points)
16.( 1) Sketch. Scoring description: 2 points for drawing right.
(2) sketch. Scoring description: correctly draw incident light and refracted light 1 minute, ***2 points.
17.( 1) The pressure of the same liquid is equal in all directions at the same depth.
(2) The pressure of the same liquid increases with the increase of depth.
(3) The pressure of different liquids at the same depth is related to the density (or the greater the density of liquids at the same depth, the greater the pressure).
Scoring description: 65438+ 0 for each blank, ***3.
18.( 1)2 Wenzhou
Physical quantity: mass of empty beaker and total mass of vegetable oil: volume of vegetable oil.
Density of vegetable oil
The measured value is 33.4 0.92×103.
(2)(2 points)
① Pour a proper amount of vegetable oil into a beaker and measure the total mass of beaker and vegetable oil m 1? ;
② Pour part of the vegetable oil in the beaker into the measuring cylinder and measure the volume V of the vegetable oil. ;
③ Measure the mass m2 of beaker and residual vegetable oil with a balance? ;
④ Calculate the density of vegetable oil.
Scoring description: the answer to this question is not unique, the design scheme is reasonable, and it can be scored.
36( 1, (3), (4), (5) 1 minute per space, (2) 1 minute for connection, ***6 points.
( 1)" 50ω0.5A "
(2) The circuit wiring is shown on the right.
(3) The "I" end of the ammeter is connected with the "D" end of the sliding rheostat.
(4)0.32; 1.92
(5) Measure the resistance of the bulb.
40. Solution: (1) Moving pulley saves labor, but it cannot change the direction of force.
(2) 0.5W
4 1.( 1) When switch S 1 is placed at terminal B and S2 is closed, it is in the low gear (2)1000 w (3) 5.4×105 j.