Where can I find the tutorial exercise of physical optics in junior high school?

Review of five physics questions in senior high school entrance examination

Pressure buoyancy

First, multiple choice questions

1. When studying the law of liquid internal pressure, Xiao Liang boldly explored and made many experiments with two liquids, A and B. According to the experimental data, he drew the image of liquid pressure changing with depth, as shown on the right, so the density relationship between A and B is (C).

A, B,

C, d, the conditions are insufficient to judge.

2, as shown in the figure is a cross-sectional view of several different channels, of which the safest and most reliable design is (D).

3. Two solid cubic metal blocks, A and B, are placed on a horizontal desktop, and their pressure acts on the desktop, so the relationship between their density and size is (A).

A, b, c, d, uncertain

4. Three solid cubes A, B and C are placed on the horizontal ground respectively, and their pressures on the horizontal ground are equal. It is known that if copper blocks with equal mass are placed on three cubes A, B and C, the pressure relationship between the three cubes and the horizontal ground is (A).

A, b, c, d, can't judge

5. The pressure of the uniform cube on the horizontal ground is, and the pressure is, as shown in the figure. If the shadow part is cut off, the pressure and pressure of the remaining part on the ground are (b) respectively.

This is a good example.

6. (Multiple-choice question) As shown in the figure, it is a cylindrical container with equal mass and a container B with a big bottom opening. Pour a proper amount of the same liquid respectively, and the liquid level is equal to the upper surface area of the liquid. Let the pressure of the liquid in the two containers at the bottom of the container be respectively, and the pressure on the desktop be respectively, then (BC)

A, B, C, D,

7. As shown in the figure, the outline of the sole of a junior high school student with a weight of 672N is drawn by standing on a square paper, in which the area of each square is 6.0cm2, and the ground pressure value of the student with both feet standing on the horizontal ground is more accurate (B).

a、 1.65× 104Pa B、2.0× 104Pa C、3.30× 104Pa D、4.0× 104Pa

8. The beaker on the horizontal table is filled with strong brine. If a certain amount of clear water is added to the beaker (without overflowing), then (c)

A, the density of brine decreases, and the liquid pressure at the bottom of beaker decreases.

B, salt water density increases, and the liquid pressure at the bottom of the beaker increases.

C, the density of brine decreases, and the liquid pressure at the bottom of beaker increases.

D, the density of brine increases, and the liquid pressure at the bottom of beaker decreases.

9. The water level at the bottom of the Three Gorges Dam is 66 meters (the water level indicates the height relative to the sea level at Wusongkou, Shanghai). The dam began to store water at 9: 00 am on June 1 0 this year, and the water level reached 135m at 5: 00 pm on June 10. If g is 10N/kg, the pressure of water on the dam bottom is (b).

a、6.6× 105Pa B、6.9× 105Pa C、 1.35× 106Pa D、2.0 1× 106Pa

10, (multiple choice questions) Summer is here. Wei Wei put ice cubes into a cup filled with cold boiled water to make a cold drink, as shown in the picture. When the ice melts, what remains unchanged is (ABCD).

A, the height of water in the cup b, the pressure of the cup on the desktop

C, the water pressure at the bottom of the cup D, the water pressure at the bottom of the cup

1 1, the weight of the metal block resting on the inclined plane is 10N, the pressure of the metal block on the inclined plane is 6N, and the contact area between the metal block and the inclined plane is 20cm2, so the pressure of the metal block on the inclined plane is ().

a、5× 103Pa B、3× 103Pa C、2× 103Pa D、8× 103Pa

12, in the figure below, the purpose is to increase the pressure ().

13, (multiple-choice questions) The displacement of submarine when sailing on the seabed is, the displacement when sailing on the sea surface is, and the density of seawater is. Try to judge which of the following statements is correct ().

A, when it is sailing on the seabed, the buoyancy is equal to

B, the pressure difference when it sails on the seabed.

When the submarine is sailing at sea, the volume of the underwater part is

D. Submerge the submarine into the seawater to be filled with seawater.

14 someone sucked the air out of a small empty bottle with their mouth, and the bottle hung on their mouth immediately because ().

A, the mouth sucks the bottle b, and the result of residual air in the bottle.

C. The saliva on the mouth sticks to the bottle D. The small bottle is pressed on the lips at atmospheric pressure.

This year marks the 0/00th anniversary of successfully climbing Mount Everest/KLOC-. Although we haven't been to Mount Everest, we can know from the knowledge that the atmospheric pressure changes with height that the atmospheric pressure at the summit may be ().

A, 30 kPa B, 80 kPa C, 100 kPa D, 120 kPa

16, when we breathe in, the following statement is true ()

A, lung volume decreases, lung pressure increases. B, lung volume increases, lung pressure decreases.

C, lung volume increases, lung pressure increases D, lung volume decreases, lung pressure decreases.

17, (multiple choice questions) A container is filled with water, and after a small ball is gently put in, 50g of water overflows, so the following judgment is correct ().

A, the quality of the ball is absolutely not less than 50g.

B the mass of the ball must be equal to 50g.

C. If the mass of the ball is greater than 50g, the volume of the ball must be equal to 50cm3.

D. If the mass of the ball is equal to 50g, the volume of the ball must be greater than 50cm3.

18, submarine from stealth to floating, before the surface, the pressure and buoyancy of seawater change correctly is ().

A, the pressure decreases, and the buoyancy remains unchanged; B, the pressure increases and the buoyancy remains unchanged.

C, constant pressure, high buoyancy D, constant pressure, low buoyancy.

19 As shown in the figure, an object with uniform mass is suspended in the water, and now it is cut into two pieces with different sizes along the dotted line and still put in the water, then ().

A, large pieces of sinking, small pieces of floating; B, big drift, small drift.

C, both pieces are suspended; D, both pieces have sunk.

20, swimmers from the river to the deep water in the process, if the bottom of the river is covered with gravel, then ()

A, my feet are getting more and more painful, because the water is putting more and more pressure on my feet.

B, the feet are getting less and less painful, because the bottom of the river has less and less support for people.

C, feet are getting more and more painful, because water is more and more buoyant to people.

D, foot pain is getting lighter and lighter, because people's gravity is getting smaller and smaller.

2 1, a solid object is hung under the spring dynamometer, and the pointer of the spring dynamometer is F. If the object is immersed in water, the pointer of the spring dynamometer is static, and the density of the object is ().

A,1.0×103kg/m3 b, 0.8×103kg/m3 c,1.5×103kg/m3 d,1.25.

22, when the object is in a free state in deep enough water, the following statement is incorrect ().

1. Objects whose density is greater than that of water will sink to the bottom of the water.

B, the density of water is greater than that of water objects may also float on the water.

C, the density is less than water objects must be in a floating state.

D, if it is the same quality of wood and iron, the buoyancy of wood is greater than iron.

Second, fill in the blanks

1. The pressure of a tank on the ground is 2× 105Pa, and its physical meaning is _ _ _ _ _ _ _ _.

2. Careful Zheng found that the kitchen knife at home had been used for a period of time, and his father wanted to grind it to reduce _ _ _ _ _ _ _ _ _ _ _ _, so as to achieve the purpose of increasing _ _ _ _ _ _.

3. The deeper the submarine dives into the water, the pressure of the water will be _ _ _ _ _ _ _, and the pressure of the water on the submarine will be _ _ _ _ _ _ _ _ _ _, so there is a certain limit to _ _ _ _ _ _.

4. Put the metal box of the same pressure gauge into clear water and salt water with the same depth, and find that the pressure is in _ _ _ _ _ _ _ _.

When Xiao Wei took part in military training, the physical examination showed that his weight was 50 kilograms. When standing at attention, his pressure on the horizontal ground _ _ _ _ _ _ _ _ _ n；; When he walks forward, his pressure on the horizontal ground will be _ _ _ _ _ _ (fill in "increase", "unchanged" or "decrease").

6. As shown in the figure, two fingers hold the pencil hard to keep it still, so the pressure on the two fingers is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

7. As shown in the figure, it is an image of the relationship between the pressure and depth of liquids A and B drawn by a classmate when studying the pressure of liquids. As can be seen from the figure, the density relationship between liquid A and liquid B is _ _ _ _ (fill in ">", "< or =", in which _ _ _ _ _ liquid is water.

8. The vacuum cleaner is a modern cleaning tool that uses _ _ _ _ _ _ _. Not only used in hotels and restaurants, but also gradually entered the homes of ordinary people.

9. When cooking milk, in order to maintain the nutritional content of milk, you can't cook it at high temperature. To this end, people made a "low-pressure pot". Boiling milk in this pot can make the water in the milk boil below 100℃. The physical principle of this "low-pressure boiler" is _ _ _ _ _ _.

10 Usually, people regard the pressure generated by a mercury column with a height of _ _ _ _ cm as 1 standard atmospheric pressure, which is closely related to the weather. Generally speaking, the air pressure in sunny days is higher than that in cloudy days, and the air pressure in winter is higher than that in summer.

1 1. Please fill in the blanks with the following option codes (the codes can be reused).

A. rising; B. reduce; C. high temperature; D. low temperature; E. good conductor; F. poor conductor; G. insufficient dissolved oxygen in water; H. dissolved oxygen in water is sufficient.

Meteorological forecast is of great significance to people's life, industrial and agricultural production, military, scientific research and other industries. At present, weather forecast has developed into a long-term weather forecast using supercomputers. But people can also make short-term weather forecasts by observing natural phenomena, such as observing the floating state of fish in a pond. When a large number of fish are found floating on the water surface in the pond, when they breathe heavily, it often indicates that it is going to rain, because where it is going to rain, the atmospheric pressure is often _ _ _ _ _ _ _ _ _ _ _ _ _ _, which makes the solubility of oxygen in water _ _ _ _ _ _ _ _ _ _, forcing the fish to float on the water surface and breathe. But this kind of situation often occurs in the pond when it rains in summer, and rarely occurs in the pond when it rains in winter. This is because the pond water temperature is high in summer, which is rare in lakes with deep water in summer. This is because the water is hot, and the water in the deep lake is still _ _ _ _ _ _ _.

12. When spraying the liquid medicine with the watering can as shown in the figure in the classroom, first pump air into the pot with the pump set on the watering can, and then open the valve to spray the liquid medicine. Pump air into the kettle so that the air pressure above the liquid level in the kettle is _ _ _ _ atmospheric pressure (fill in "greater than", "equal to" or "less than"); After spraying the potion, you can smell the potion around the classroom, which is caused by _ _ _ _ _.

13. Weigh two iron blocks and aluminum blocks in the air, and the numbers displayed by the spring scale are the same. If the iron and aluminum blocks are submerged in water, the spring scale called _ _ _ _ _ _ shows a larger number. If you weigh in vacuum, the spring scale weighing _ _ _ _ _ _ _ _ has a larger indication.

14. When a ship has a displacement of 8,000 tons, the buoyancy it receives when it is fully loaded is _ _ _ _ n. If its maximum cargo capacity is 5,000 tons, but it actually only carries 4,000 tons, then the buoyancy it receives is _ _ _ _ _ n. (g =1.

Jiaozi is everyone's favorite food. Jiaozi, who just entered the water, sinks to the bottom, cooks in the water for a while and then floats. This is because jiaozi is heated by _ _ _ _ _ _ _ _ _ _.

16, put an object with a volume of 250 cm 3 into a container filled with water, and the overflow volume of water is 200 cm 3. So, the ups and downs of this object in the water is _ _ _ _ _ _ cattle, and the density of the object is _ _ _ _ _ kg/m3.

17. Put an object with a volume of 2m3 and a density of 0.5× 103kg/m3 into the water. When an object is at rest in water, it will be buoyed by _ _ _ _ _ n. If it is put into a liquid with a density of 0.4× 103kg/m3, it will be at rest.

18. Balloons and airships rose into the air by _ _ _ _ _ _. If the total weight of the balloon is _ _ _ _ _ _ _ _, the balloon will rise. If the balloon drops _ _ _ _ _ _ _ _.

19. Half of the objects suspended on the spring scale are submerged in water, and the pointer of the spring scale is lower than that before the objects are submerged in water1n. The volume of this object is _ _ _ _ _ _. When all objects are submerged in water, the pointer of the spring scale is 3N, and the weight of the objects is _ _ _ _ _ _ _.

20. There is an object hanging at the lower end of the spring scale, and all the objects are immersed in the water. The buoyancy is 0.49N, the pointer of the spring balance is 0.83N, the weight of the object is _ _ _ _ _ _ N, and the volume of the object _ _ _ _ _ _ _ _ _ m3. If you put this object in mercury, the buoyancy is _ _ _ _ _ _ _.

2 1. Submarines can float by changing the position of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The buoyancy is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Third, the experimental questions

1, in order to explore "what is the internal pressure of the liquid related to it", some students put forward the following conjecture:

Guess 1: the pressure inside the fluid may be related to the depth of the liquid;

Conjecture 2: The pressure of liquid may be different at the same depth and in different directions;

Conjecture 3: The pressure inside the liquid may be related to the density of the liquid.

In order to verify the above conjecture 1 and conjecture 2, they studied the pressure inside the water with a manometer and obtained the following data:

Serial number 1 2 3 4 5 6 7 8 9

Depth (cm) 55510101515.

Up and down sides, up and down sides, up and down sides in the direction of rubber film.

The liquid level difference (cm) of the pressure gauge is 4.34.34.39.29.29.213.813.813.8.

① Please analyze the experimental data and answer:

In order to verify the conjecture 1, the experimental data with serial number _ _ _ _ _ _ _ _ should be selected; The conclusion of conjecture 2 is _ _ _ _ _.

In order to verify the correctness of conjecture 3, please design an experimental inquiry scheme and write out the experimental steps on the basis of the above experiments.

2. When exploring what the role of stress is related to, a classmate did three experiments as shown in the figure, and showed the role of stress by observing the bubbles in the three experiments. Compared with the experiment shown in Figure _ _ _ _ _, it can be seen that the greater the pressure, the more obvious the pressure effect under the same stress area. Compared with the experiment shown in Figure _ _ _ _ _ _, it can be seen that the smaller the stress area is, the more obvious the pressure effect is under the same pressure.

3. Two cylindrical containers A and B with the same volume are filled with water and placed on a horizontal table. As shown in the figure, the pressure of water on the bottom of the two containers A and B and the relationship between the pressures are _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 、"=")

4. In order to find out which factors are related to the influence of solid cylinders on horizontal ground pressure, a classmate placed several different cylinders vertically on the same horizontal sand surface, conducted three groups of experiments, and recorded relevant data, as shown in Table 1, Table 2 and Table 3 respectively. In the experiment, he carefully observed the depression degree of the sand surface. Through comparison, he found that the depression degree of each group was the same, but each group was different. The first group was the most depressed, followed by the second group, and the third group was the least.

Table1(= 8.9×103kg/m3)

Experimental serial number Material height (cm) Bottom area (cm2)

1 copper 20 10

2 copper 20 20

3 copper 20 30

Table 2(= 7.8× 103 kg/m3)

Experimental serial number Material height (cm) Bottom area (cm2)

4 Tie20 10

5 iron 20 20

6 iron 20 30

Table 3(= 8.9× 103 kg/m3)

Experimental serial number Material height (cm) Bottom area (cm2)

7 copper 20 10

8 copper 20 20

9 copper 20 30

(1) By analyzing and comparing the data of the experimental serial number 1, 2,3 (or 4,5,6 or 7,8,9) with the observed phenomena, a preliminary conclusion can be drawn: when the density and height of cylindrical materials are the same, the effect of pressure is the same as the bottom area. (Select "relevant" or "irrelevant")

⑵ By analyzing and comparing the data of the experimental serial number _ _ _ _ with the observed phenomenon, we can draw a preliminary conclusion: when the cylinder height is the same, the greater the density of the substance, the more obvious the effect of pressure.

(3) By analyzing and comparing the data of serial numbers 1 and 7 (or 2 and 8, or 3 and 9) with the observed phenomena, we can draw a preliminary conclusion that it is _ _ _ _ _ _ _.

(4) (a) By analyzing and comparing the data in Table 1, Table 2 and Table 3 and the observed phenomena, we can preliminarily draw the following conclusions: _ _ _ _ _ _ _ _ _

___________________________________。

(b) By analyzing and comparing the data in Table 1, Table 2 and Table 3 with the observed phenomena, we can preliminarily draw the conclusion of _ _ _ _ _ _.

___________________________________。

5. Scientists found through experiments that for a certain mass of gas, the law of pressure changing with temperature has the following data under the condition of constant volume:

Experimental sequence 1 2 3 4 5

Gas temperature t/℃

Gas pressure p/103pa10010120130140.

Analyze the data and give the relationship between p and t.

6. In the activities of the physics extracurricular group, the teacher took out a measuring cylinder with a row spacing of 1mm and an empty small glass bottle with a thick bottom, which could be put into the measuring cylinder. The teacher asked the students to use these things to measure the density of this glass material made of glass bottles with the help of things commonly used in daily life. Xiao Ming thought for a moment, then poured some water into the measuring cylinder, put the measuring cylinder on a horizontal table and recorded that the water depth in the measuring cylinder was 22.0cm. Then put the bottle mouth of the empty bottle upward into the measuring cylinder, and the empty bottle can float upward on the water. Xiao Ming measured from the scale line, and the water depth in the measuring cylinder was 28.0 cm. Xiao Ming then presses the empty bottle into the water. When the bottle was filled with water and sank to the bottom of the measuring cylinder, the water level in the measuring cylinder was just flush with the scale line of 24.2cm. According to the experimental data and the known density of water, Xiao Ming quickly calculated the density of glass materials. Please tell me how Xiao Ming solved this problem. He measured the density of glass materials.

Fourth, question and answer.

1, the earth is our "home" for human survival, and the atmosphere is the umbrella of the military "home". Without it, human beings will not survive. Please imagine that if there is no atmosphere around the earth, nothing will happen in the relevant physical experiments and examples involved in the textbook. (Write at least three phenomena)

2. Some sports cars have designed and installed "air deflector" at the rear. Its upper surface is straight, and its bottom is isolated and convex, which is equivalent to an inverted wing. This is mainly to make the wheels of sports cars grip the ground better when driving at high speed. Please explain the reason.

3. "Cupping" is a method used by ordinary people to treat low back and leg pain caused by cold. The specific way is to heat the air in the jar, then quickly buckle it on the skin of the painful part, and hold down the jar. After a while, the jar will "suck" on the skin to explain the reason.

Xiao Xin and her classmates are playing in the street. Xiao Xin found new coconuts in the street. But strangely enough, the salesman always makes two holes in the coconut. One is for inserting straws, and the other is for what? Can you explain it?

Verb (abbreviation of verb) calculation problem

1. Xiaogang's mother bought a box of milk and put it on the floor. The contact area between the box and the floor is 0.025cm2, and the total mass of the box and milk is 5kg. Every small bag of milk in the box is marked with the words "net content 22 1ml, 227g". (g= 10N/kg)

Ask: (1) What is the density of this milk? (Two decimal places are reserved for the calculation result)

What is the pressure of this box of milk on the floor?

The municipal government will build a sculpture in the square. The mass of the sculpture is 6.0× 104kg, and the bottom is designed as a rectangle with a length of 2m and a width of1.4m.

Q: (1) What is the gravity on this sculpture?

⑵ What is the pressure of sculpture on the horizontal base?

3. The mass of someone is 6 1.8kg, and the density is1.0x103kg/m3. He fished out a closed metal box with a volume of 0.02m3 on an inflatable raft weighing 103N (people were on the raft). When fishing, the force for this person to pull the box (the box is in the water) at a constant speed is 4 1.2N, and the density of seawater is1.03x103kg/m3 (take g= 10N/kg).

(1) What is the gravity of the metal box?

(2) If a person puts a metal box on the hovercraft and holds the hovercraft with his hands, when he is at rest (when he is in water), his body volume is above the water surface. What is the volume of the hovercraft in seawater?

1. 1, C 2, D 3, A 4, A 5, B 6, BC 7, B 8, C 9, B 10, ABCD 1 1, a.

12、B 13、CD 14、D 15、A 16、B 17、AC 18、A 19、C 20、B 2 1、D 22、A

2. 1. The pressure per square meter of the tank on the ground is 2× 105N 2, the stress area, the pressure 3, the greater the depth 4, the salt water 5, 490, the increase 6, equal to or unequal to 7, >, B 8, atmospheric pressure 9, and the lower the liquid surface pressure. The lower the boiling ratio of liquid is 10, 76, 1 1, b, b, g, F7× 107 15, the expansion, the increase 16, and the floating, 2.08. 8× 103 18, buoyancy, 5N 20, 1.32, 5× 10-5, 1

1, ① 1, 4,7 (or 2,5,8 or 3,6,9) The pressure of the same liquid at the same depth is equal in all directions.

②a change the water in the above experiment into salt water (or other liquid), b measure and record the liquid level difference between the two tubes of the pressure gauge when the rubber film is 5cm, 10cm and 15cm below the liquid level, and c compare the data recorded by salt water (or other liquid) and water at the same depth to draw a conclusion.

2. Depth (or deformation size) of pressing (a)(c), (a)(b)

3 、=、& lt

4, (1) Independent (2) 1 and 4 (or 2 and 5, or 3 and 6) (3) When the cylinder materials are the same, the higher the height, the more significant the pressure effect (4) (a) The product of the cylinder material density and height is the same, and the pressure effect is the same. (b) The greater the product of the density and height of cylindrical materials, the more significant the influence of pressure.

5、p=0.4t+ 100

6. 2.73× 103 kg/m3

1, ① The phenomenon of Torricelli experiment will not happen again. (2) The phenomenon that sound propagates through the air no longer occurs. (3) the pump can't pump water. (4) The sun shines on the surface of the earth without refraction. ⑤ Do not stick the plastic sucker on the smooth wall. 6. Hydrogen balloons can't be launched. ⑦ Internal combustion engine can't work.

2. When the airflow speed on the lower side of the deflector is higher than that on the upper side, the pressure on the lower side is lower than that on the upper side, and the car is tightly pressed to the ground.

3. When the air in the tank is heated, due to thermal expansion, part of the air runs out of the tank, and the tank is buckled on the skin to seal the air in the tank. When the temperature decreases, the air pressure in the tank decreases and becomes less than the atmospheric pressure. Because the air pressure outside the tank is greater than the air pressure inside the tank, the tank is pressed against the skin.

4. Opening an extra hole can ensure that the interior is always connected with the atmosphere. Under the action of atmospheric pressure, the air pressure in coconut is always greater than that in straw, so it is easier to suck coconut juice.

Verb (abbreviation of verb) 1, (1)1.03g/cm3 2×103pa2, (1) 5.88×105n2./kloc-