Experimental device for exploring relationship between pressure of liquid on bottom of container and shape of container
By designing an experimental device for measuring the pressure of liquid on the bottom of containers of different shapes, it solves the problem of students understanding the relationship between liquid pressure and container shape, achieves intuitive and perceptual learning effects, and reduces the difficulty of physics learning.
Patent Information
- Application Number
- CN202323344005.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-08
- Publication Date
- 2025-01-17
- Estimated Expiration
- 2033-12-08
AI Technical Summary
Students have difficulty understanding and lead to obstacles to physical learning when learning the relationship between the pressure of liquids to the bottom of containers with different shapes.
Design an experimental device, including three containers with the same bottom area but different shapes. The container's own gravity and the pressure of the liquid on the bottom of the container are measured using a tension gauge and a platform scale. The shape of the container is adjusted to observe the pressure change.
Through intuitive experimental methods, it helps students understand the relationship between liquid and pressure at the bottom of containers of different shapes, reduces learning difficulty, and promotes the learning of physics subjects.
Smart Images
Figure CN222365323U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of teaching instruments, and in particular relates to an experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container. Background Art
[0002] Pressure is an important teaching content of middle school physics, among which liquid pressure is a difficult point to learn. For example, the following are the types of questions that students are easily confused about, and they are also the must-learn knowledge points that students must master:
[0003] like Figure 1 As shown: There are three containers with the same bottom area, equal mass, but different shapes placed on a horizontal table, namely wide-mouth container 1, vertical container 2, and narrow-mouth container 3. Different liquids of equal depth and mass are placed in the containers, and the gravity of the liquid is G. The pressure of the liquid on the bottom of the three containers is P respectively. 1 , P 2 , P 3 , the pressure of the liquid on the bottom of the three containers are: F 1 、F 2 、F 3 The pressures of the three containers on the desktop are P1', P 2 ' 、P 3 ', the pressure of the container on the desktop is: F 1 '、F 2 '、F 3 ', try to compare their sizes respectively, and fill in the ﹥﹤= symbols in the following horizontal lines:
[0004] P 1 P 2 P 3 , F 1 F 2 G F 3 ,
[0005] P 1 ' P 2 ' P 3 ', F 1 ' F 2 ' F 3 '.
[0006] Analysis (1), pressure inside the container:
[0007] The volume of liquid in wide-mouth container 1 is the largest, and the volume of liquid in narrow-mouth container 3 is the smallest. 1 ﹥V 2 ﹥V 3 , the masses are equal, indicating that the density ρ 1 ﹤ρ 2 ﹤ρ 3 , according to the liquid pressure formula, P = ρgh, P 1 ﹤P 2 ﹤P 3 , and from F=P·S, we know that F 1 ﹤F 2 ﹤F 3 Since the vertical container 2 is vertical, the gravity of the liquid acts entirely on the bottom of the container, so F 2 =G. So we have F 1 ﹤F 2 =G﹤F 3 .
[0008] Analysis (2), the pressure of the container on the desktop:
[0009] The pressure of a solid has nothing to do with its shape. Regardless of its shape, if it is placed on a horizontal surface, the pressure it exerts on the table is equal to the weight of the container as a whole. This weight consists of two parts: one is the weight of the container itself, and the other is the weight of the liquid. In the question, the masses of the containers are equal, and the weights of the liquids in the containers are also equal, so we have F 1 ' = F 2 ' = F 3 '.
[0010] In the above analysis, the difficulty for students to understand is that when analyzing the pressure inside the container, why should we first use the liquid pressure formula P=ρgh to compare the size of the liquid pressure, and then use F=P·S to compare the size of the pressure of the liquid on the bottom of the container, instead of first deriving that pressure is equal to gravity and then analyzing the pressure. When analyzing the pressure of the container on the table, why should we first compare the pressure and then compare the size of the pressure.
[0011] The reasons for the above-mentioned comprehension barriers of students are:
[0012] It is easy to understand that in the vertical container 2, the pressure F of the liquid on the bottom of the container 2 is equal to the gravity G of the liquid; what is a little difficult to understand is that in the wide-mouth container 1, the pressure F of the liquid on the bottom of the container 1 is smaller than the gravity G of the liquid; it is difficult to understand that in the narrow-mouthed container 3, the pressure F of the liquid on the bottom of the container 3 Greater than the gravity of the liquid G. That is, students do not understand the pressure transmission of liquids to containers of different shapes.
[0013] So the teacher had to do Figure 2 Theoretical explanation shown:
[0014] In the vertical container 2, the gravity of the liquid is all pressed on the bottom of the container, and the gravity of the liquid is equal to the pressure of the liquid on the bottom of the container.
[0015] In the wide-mouth container 1, only the liquid weight within the vertical cylindrical surface (dashed line in the figure) where the bottom area is located acts on the bottom surface of the container, and the liquid weight outside acts on the container wall. Therefore, the liquid weight is greater than the pressure of the liquid on the bottom of the container.
[0016] In the narrow-mouth container 3, the gravity of the liquid acts entirely on the bottom of the container, and there is also a reaction force from the container wall to the liquid pressure. Because the container wall is inclined downward, the container wall has a downward component of force on the liquid, which also acts on the bottom of the container, so the gravity of the liquid is less than the pressure of the liquid on the bottom of the container.
[0017] Many students still find it difficult to understand this explanation, which makes them difficult to learn physics, especially the common question types mentioned above, which have many variations.
[0018] Variation 1: Change to the same liquid with the same density, such as Figure 1 As shown in the figure, there are three containers with the same bottom area and mass placed on a horizontal table, namely wide-mouth container 1, vertical container 2, and narrow-mouth container 3. The same liquid is filled into the three containers with the same depth. The pressure of the liquid on the bottom of the container is P 1 , P 2 , P3; the pressure of the liquid on the bottom of the container is: F 1 、F 2 , F3, the pressures of the three containers on the desktop are: P 1 ' 、P 2 ', P3', the pressures of the three containers on the desktop are: F 1 '、F 2 '、F3'. Try to compare their sizes respectively and fill in the ﹥﹤= symbols in the following horizontal lines:
[0019] P 1 P 2 P 3 , F 1 F 2 F 3 ,
[0020] P 1 ' P 2 ' P 3 ', F 1' F 2 ' F 3 '.
[0021] Variation 2: A mineral water bottle is half filled with water, that is, the water level in the bottle does not reach the oblique part below the bottle mouth, the bottle body is vertical, the area of the bottle cap is much smaller than the area of the bottle bottom, and the bottle cap is tightened. When the mineral water bottle is placed upright on a horizontal table, the pressure of water on the bottom of the bottle (Select size, less than, equal to) the gravity of water; when a mineral water bottle is placed upside down on a table, the pressure of water on the bottle cap (Select size, less than, equal to) the gravity of water. When the mineral water bottle is placed from upright to inverted on the table, the pressure of the mineral water bottle on the table will be (Optional: change size, become smaller, remain unchanged).
[0022] Since there are many similar question types mentioned above, and they are required knowledge points, it is difficult for students to understand them. Experiments are needed to verify the relationship between the pressure of the liquid on the bottom of the container and the gravity of the liquid in containers of different shapes, so as to help students establish perceptual understanding and reduce the difficulty of learning. Utility Model Content
[0023] In order to solve the above technical problems, the utility model provides an experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container.
[0024] The technical solution adopted by the utility model to solve the above technical problems is:
[0025] An experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container, comprising three containers with the same bottom area and an opening at the top, which are a wide-mouth container with a wide top and a narrow bottom, a vertical container with the same width at the top and the bottom, and a narrow-mouth container with a narrow top and a wide bottom. The device is characterized in that it also comprises a bracket, a tensiometer fixed on the bracket, and a platform scale placed on a desktop, wherein the upper side walls of the containers are provided with hanging holes for connecting hanging ropes, and the containers are hung under the tensiometers through the hanging ropes to measure the gravity of the containers; the bottom of the containers is open and covered with a flexible film, so that the containers become containers that can hold liquids; the platform scale is placed under the containers, and lifting screws are installed at the bottoms of both ends of the brackets, and the lifting screws can be adjusted to lift the containers, so as to adjust the gap between the containers and the platform scale below, so that the gravity of the container wall is completely borne by the tensiometer, and the platform scale only bears the liquid pressure transmitted by the upper flexible film. When the container is filled with liquid, the platform scale can measure the pressure of the liquid on the bottom of the container, and the relationship between the pressure of the liquid on the bottom of the container and the shape of the container can be studied by replacing containers of different shapes for experiments.
[0026] The container is made of a transparent material, and the flexible film is a rubber film or a plastic film.
[0027] or:
[0028] The invention relates to an experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container, comprising a container with an opening at the top, characterized in that it also comprises a bracket, a dynamometer fixed on the bracket, and a table scale placed on a desktop, wherein the upper side wall of the container is provided with a hanging hole for connecting a hanging rope, and the container is hung on the dynamometer below the bracket by the hanging rope to measure the gravity of the container; the container comprises two vertical plates, a lower connecting plate fixed between the vertical plates and located at the lower ends of both sides thereof, an upper connecting plate fixed between the vertical plates and located at the upper ends of both sides thereof, and two inner connecting plates fixed between the vertical plates and located at the inner sides of the upper ends thereof, two left and right movable side plates are respectively placed between the vertical plates and between the upper connecting plate and the inner connecting plate, and a hinged connecting structure is provided between the lower end of the movable side plate and the lower connecting plate so that The movable side plate can use the lower end as an axis, and its upper end can be rotated to the left or right between the upper connecting plate and the inner connecting plate, so as to change the inclination angle of the left and right side walls of the container; the bottom of the container is open, and a flexible bag is placed in the container, and the front and rear outer walls of the flexible bag are respectively pasted on the inner walls of the adjacent vertical plates, and the left and right outer walls of the flexible bag are respectively pasted on the inner walls of the two movable side plates, and the bottom of the flexible bag is exposed at the bottom of the container. When the flexible bag is opened, the container becomes a deformable container that can hold liquid and has variable inclination angles of the two side walls; the platform scale is placed below the container, and lifting screws are installed at the bottom of both ends of the bracket. The container can be raised and lowered by adjusting the lifting screws to adjust the gap between the container and the platform scale below, so that the gravity of the container wall is borne entirely by the dynamometer, and the platform scale only bears the liquid pressure transmitted by the upper flexible bag to measure the pressure of the liquid on the bottom of the container; by adjusting the inclination angles of the two side walls of the deformable container, the relationship between the pressure of the liquid on the bottom of the container and the shape of the container can be studied.
[0029] The container is made of transparent material, and the flexible bag is a plastic bag or a rubber bag.
[0030] Compared with the prior art, the utility model has the following beneficial effects:
[0031] 1. Use the dynamometer above the container to measure the gravity of the container itself, and use the scale below the container to measure the pressure of the liquid on the bottom of the container. When the container wall is vertical, it can be directly measured that the pressure of the liquid on the bottom of the container is equal to the gravity of the liquid.
[0032] 2. When using a wide-mouth container (or a deformable container with the movable side panels tilted outward), it is observed that the reading on the scale is decreasing, which is obviously less than the gravity of the liquid. At the same time, it is found that the reading on the upper dynamometer is increasing, indicating that the "reduced" pressure of the liquid on the bottom of the container is transferred to the side wall of the container. Then, it is intuitively understood that in a wide-mouth container, the pressure of the liquid on the bottom of the container is less than the gravity of the liquid.
[0033] 3. When using a narrow-mouth container (or a deformed container with the movable side panels tilted inward), you can see that the reading on the scale is increasing, which is obviously greater than the gravity of the water, while the reading on the dynamometer is decreasing. This helps students understand that the two sides of the liquid exert an upward force on the left and right side walls of the container, and the left and right side walls of the container exert a downward reaction force on the liquid. This reaction force is transmitted to the bottom of the container through the liquid, so in a narrow-mouth container, the pressure on the bottom of the container is greater than the gravity of the liquid.
[0034] 4. If a deformable container is used, it is also possible to observe the gradual change in the pressure of the liquid on the bottom of the container as the shape of the container gradually changes:
[0035] Keep the amount of water constant and pull the wire inward to slowly move the two movable side panels from outside to inside. That is, as the container gradually changes from a wide mouth to a narrow mouth, it can be observed that the pressure of the liquid on the bottom of the container (the scale reading) gradually increases, and the dynamometer reading (the gravity of the container and the downward pressure of the liquid on the container side wall) gradually decreases. Pull the wire in the opposite direction, and the readings of the scale and dynamometer will change in the opposite direction. This will intuitively establish the relationship between the pressure of the liquid on the bottom of the container and the shape of the container in the minds of students.
[0036] 5. The above experimental effect is very obvious. It allows students to intuitively feel the relationship between the pressure of the liquid on the bottom of the container and the gravity of the liquid when the shape of the container is different, understand the relationship between the pressure of the liquid on the bottom of the container and the shape of the container, reduce the difficulty of learning, and promote the learning of physics. BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Figure 1 It is a schematic diagram of the existing test questions;
[0038] Figure 2 It is the principle analysis diagram of the existing test questions;
[0039] Figure 3 It is a structural schematic diagram of the first embodiment of the utility model;
[0040] Figure 4 It is a structural schematic diagram of a specific embodiment 2 of the utility model;
[0041] Figure 5 It is a schematic structural diagram of a deformable container according to a second specific embodiment of the utility model (the plastic bag sleeved inside is not shown).
[0042] In the figure: 1 wide-mouth container, 2 vertical container, 3 narrow-mouth container, 4 scale, 5 load-bearing plate, 6 flexible membrane, 7 lifting screw, 8 bracket, 9 dynamometer, 10 hanging rope, 11 hanging hole, 12 cushion strip, 13 vertical plate, 14 adhesive strip, 15 lower connecting plate, 16 movable side plate, 17 plastic bag, 18 upper connecting plate, 19 vertical identification line, 20 inner connecting plate, 21 pull wire. DETAILED DESCRIPTION
[0043] like Figure 3 As shown, the utility model includes three containers with the same bottom area and openings on the top, namely a wide-mouth container 1 with a wide top and a narrow bottom, a vertical container 2 with the same width at the top and bottom, and a narrow-mouth container 3 with a narrow top and a wide bottom. The bottoms of the three containers are not open at the bottom, so that it is convenient to cover the bottom of the container with a flexible film 6, so that the container can be a container for holding liquid. The upper side walls of the containers are each provided with a hanging hole 11 for connecting a hanging rope 10.
[0044] Since the outer walls of the wide-mouth container 1 and the narrow-mouth container 3 are both inclined, in order to prevent the flexible film 6 from slipping, one way is to glue the flexible film 6 to the outer wall of the bottom of the container; another way is to fix a circle of oblique pads 12 on the outer walls of the bottom of the wide-mouth container 1 and the narrow-mouth container 3 to make their outer walls flat and vertical, and to set grooves on the outer walls of the pads 12, so that the flexible film 6 can be conveniently directly sleeved on the outer wall of the bottom of the container with a rubber band.
[0045] A dynamometer 9 is fixed on the bracket 8, and a container ( Figure 3 In the figure, there is a vertical container 2, and a platform scale 4 is placed under the container, which is placed on the table. Lifting screws 7 are installed at the bottom of both ends of the bracket 8. The lifting screws 7 are adjusted to lift the container to adjust the gap between the container and the load plate 5 on the platform scale 4 below, so that the gravity of the container wall is completely borne by the tensile gauge, and the platform scale only bears the liquid pressure transmitted by the upper flexible film 6. When the container is filled with liquid, the platform scale can measure the pressure of the liquid on the bottom of the container. By changing containers of different shapes for experiments, the relationship between the pressure of the liquid on the bottom of the container and the shape of the container can be studied. The container can be made of PVC transparent material, and the flexible film can be a rubber film or a plastic film.
[0046] Directions:
[0047] 1. If Figure 3 As shown, hang the vertical container under the dynamometer, place a scale under the vertical container, adjust the lifting screw to lift the container to adjust the gap between the container and the scale below, so that the gravity of the container wall is borne entirely by the dynamometer, and the scale only bears the liquid pressure transmitted by the flexible membrane above, press the "tare" button on the scale so that the scale reading is zero.
[0048] 2. Take a certain amount of water (or other liquid), measure the gravity of the water and record it.
[0049] 3. Pour water into the vertical container. You can see that the indication of the dynamometer remains unchanged, while the indication of the scale keeps increasing. Finally, the force measured by the scale is equal to the gravity of the water.
[0050] 4. Replace the container with wide-mouth container 1, repeat the above experimental steps, and still inject the same amount of water. It can be seen that the reading of the balance is obviously smaller than the gravity of the water, while the reading of the dynamometer is increasing. This helps students intuitively realize that in a wide-mouth container, the gravity of the liquid only acts on the bottom of the container within the vertical cylinder where the bottom area is located, and the gravity of the outer part of the liquid acts on the container wall. Therefore, the gravity of the liquid is greater than the pressure of the liquid on the bottom of the container.
[0051] 5. Replace the container with a narrow-mouth container, repeat the above experimental steps, and still inject the same amount of water. You can see that the reading on the scale is significantly greater than the gravity of the water, while the reading on the dynamometer is decreasing. This helps students intuitively realize that the gravity of the liquid not only acts entirely on the bottom of the container, but also the reaction force of the container wall to the liquid pressure. The component of this reaction force is downward, and through the transmission of the liquid, it also acts on the bottom of the container. Therefore, the gravity of the liquid is less than the pressure of the liquid on the bottom of the container. Specific embodiments
[0052] The multiple containers of different shapes in the above-mentioned specific embodiment 1 can be replaced by a deformable container in the embodiment 2. The characteristic of the deformable container is that the two vertical plates located at the front and rear of the container are fixedly connected by a connecting plate, and the movable side plates located on the left and right sides can rotate left and right with the bottom end as the axis, thereby changing the shape of the container. When a plastic bag is put inside the deformable container, it becomes a container that can hold liquid.
[0053] like Figure 4 , Figure 5 As shown, the container is composed of a fixed mechanism and a movable mechanism. The fixed mechanism is composed of two vertical plates 13 located at the front and rear, a lower connecting plate 15 fixed between the vertical plates 13 and located at the lower ends of both sides thereof, an upper connecting plate 18 fixed between the vertical plates and located at the upper ends of both sides, and two inner connecting plates 20 fixed between the vertical plates and located at the inner position of the upper ends. A hanging hole 11 is opened on the vertical plate 13 to connect the hanging rope 10.
[0054] like Figure 4 , Figure 5 As shown, the movable mechanism of the container is composed of movable side panels 16 located on both sides. The movable side panels 16 are located between the front and rear vertical panels 13 and also between the upper connecting panel 18 and the inner connecting panel 20. A hinge-type connection structure is provided between the lower end of the movable side panels 16 and the lower connecting panel 15. Figure 4 , Figure 5 The adhesive structure shown in the figure is that the lower connecting plate is at a certain distance from the bottom of the container, so that the upper side of the adhesive strip 14 is attached to the outer wall of the lower connecting plate 15, and the lower side of the adhesive strip 14 is attached to the outer wall of the lower end of the movable side plate 16, so that the movable side plate 16 can be rotated between the upper connecting plate 18 and the inner connecting plate 20 with the lower end as the axis. The middle part of the upper end of the movable side plate 16 is opened and tied with a pull line 21. When both movable side plates 16 are rotated outward to the position of the upper connecting plate 18, it is a wide-mouth container; when the pull line 21 is pulled inward to rotate the two movable side plates 16 inward to the position of the vertical identification line 19, the container becomes a vertical container; when the pull line 21 is further pulled inward to rotate the two movable side plates 16 inward to the position of the inner connecting plate 20, the container becomes a narrow-mouth container.
[0055] like Figure 4 As shown, a plastic bag 17 is placed in the container, and the front and rear outer walls of the plastic bag 17 are respectively pasted on the inner walls of the two vertical plates 13, and the left and right outer walls of the plastic bag are respectively pasted on the inner walls of the two movable side plates 16. The bottom of the container is open, so that the bottom of the plastic bag is appropriately exposed at the bottom of the container, so that the scale below can withstand the liquid pressure transmitted by the plastic bag, open the plastic bag, and inject the liquid into the plastic bag.
[0056] like Figure 4 As shown, a dynamometer 9 is fixed on the bracket 8, and the dynamometer 9 is hung with a container below through a hanging rope 10 and a hanging hole 11. A platform scale 4 is placed below the container, and the platform scale 4 and the bracket 8 are placed on the table. Lifting screws 7 are installed at the bottom of both ends of the bracket 8. By adjusting the lifting screws 7, the container can be raised and lowered to adjust the gap between the container and the platform scale 4 below (specifically, the load-bearing plate 5 of the platform scale), so that the gravity of the container wall is completely borne by the dynamometer 9, and the platform scale 4 only bears the liquid pressure transmitted by the upper flexible bag to measure the pressure of the liquid on the bottom of the container.
[0057] Directions:
[0058] 1. Put a plastic bag in the container and stick the outer wall of the plastic bag to the inner wall of the vertical board and the movable side board. Figure 4 Assemble the instrument as shown. Adjust the lifting screw so that the gravity of the container wall is completely borne by the dynamometer, and the platform scale only bears the liquid pressure transmitted by the plastic bag above. Press the "Tare" button on the platform scale to make the scale reading zero, and record the reading of the dynamometer.
[0059] 2. Measure a certain amount of water (or other liquid) in advance, measure the gravity of the water and record it.
[0060] 3. Turn both movable side panels inward to the position of the vertical marking line, and the container becomes a vertical container. Pour the water weighed above into the container. At this time, you can tie the outer end of the pull line to the bracket or clamp it to the bracket with a clip to free your hands for other experimental operations. At this time, you can observe that the pressure displayed on the scale is equal to the weight of the water.
[0061] 4. Keep the same amount of water, pull the pull line outward, move the movable side panel outward to the position of the upper connecting plate to make the container a wide-mouth container. Observe the reading on the scale, which is the pressure of water on the bottom of the container and count it. It is found that the pressure of water on the bottom of the container is significantly less than the gravity of the water.
[0062] So where did the "missing" water weight go? Observe that the reading on the dynamometer has increased. It turns out that the "missing" water weight is pressing on the outer wall of the container. Analyzing the data, we will find that the increase in the reading on the scale plus the reading on the dynamometer equals the weight of the water.
[0063] 5. Keep the amount of water unchanged, pull the wire inward, and when the two movable side plates rotate inward to the position of the inner connecting plate, the container becomes a narrow-mouth container. You can see that the reading on the scale is increasing, increasing to a level significantly greater than the gravity of the water. Where does this "increased" pressure on the scale come from? Observe that the reading on the dynamometer has decreased.
[0064] Therefore, during the experiment, students can intuitively and clearly understand that in a narrow-mouthed container, the gravity of the liquid not only acts entirely on the bottom of the container, but there is also a reaction force from the container wall to the liquid pressure. The component of this reaction force is downward and, through the transmission of the liquid, also acts on the bottom of the container. Therefore, the gravity of the liquid is less than the pressure of the liquid on the bottom of the container.
[0065] 6. Keep the amount of water constant and pull the wire inward to slowly move the two movable side panels from outside to inside. That is, as the container gradually changes from a wide mouth to a narrow mouth, it can be observed that the pressure of the liquid on the bottom of the container (the scale reading) gradually increases, and the dynamometer reading (the gravity of the container and the pressure on the side wall of the container) gradually decreases. Pull the wire in the opposite direction, and the readings of the scale and dynamometer will change in the opposite direction. This will intuitively establish the relationship between the pressure of the liquid on the bottom of the container and the shape of the container in the minds of students.
[0066] Description: After practical testing, in the first embodiment, since there are three containers, it is best not to use plastic bags at the bottom of the containers, because it is difficult to adjust the exposure of the plastic bags at the bottom of each container to be completely consistent, and the experimental error will be large. It is best to cover the bottom of each container with a flexible film to reduce the error. The second embodiment is a deformable container. In the process of changing the shape of the container, the exposure of the plastic bag at the bottom of the container is the same, the experimental error is small, and the effect is very good. Ordinary plastic bags in daily life can be used, which are low in price and easy to replace.
Claims
1. An experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container, comprising three containers with the same bottom area and an opening at the top, namely a wide-mouth container with a wide top and a narrow bottom, a vertical container with the same width at the top and the bottom, and a narrow-mouth container with a narrow top and a wide bottom, characterized in that: The invention also includes a bracket, a dynamometer fixed on the bracket, and a platform scale placed on a desktop. The upper side walls of the container are provided with hanging holes for connecting a hanging rope. The container is hung under the dynamometer by the hanging rope to measure the gravity of the container. The bottom of the container is open and covered with a flexible film, so that the container becomes a container that can hold liquid. The platform scale is placed under the container. Lifting screws are installed at the bottom of both ends of the bracket. The container can be raised and lowered by adjusting the lifting screws to adjust the gap between the container and the platform scale below, so that the gravity of the container wall is completely borne by the dynamometer, and the platform scale only bears the liquid pressure transmitted by the upper flexible film. When the container is filled with liquid, the platform scale can measure the pressure of the liquid on the bottom of the container. By replacing containers of different shapes for experiments, the relationship between the pressure of the liquid on the bottom of the container and the shape of the container can be studied.
2. An experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container as claimed in claim 1, characterized in that: The container is made of a transparent material, and the flexible film is a rubber film or a plastic film.
3. An experimental device for exploring the relationship between the pressure of a liquid on the bottom of a container and the shape of the container, comprising a container with an upper opening, characterized in that: The container is hung on the dynamometer below the bracket by the hanging rope to measure the gravity of the container; the container includes two vertical plates, a lower connecting plate fixed between the vertical plates and located at the lower ends of both sides thereof, an upper connecting plate fixed between the vertical plates and located at the upper ends of both sides thereof, and two inner connecting plates fixed between the vertical plates and located at the inner sides of the upper ends thereof, two left and right movable side plates are placed between the vertical plates and between the upper connecting plates and the inner connecting plates respectively, a hinged connecting structure is provided between the lower end of the movable side plate and the lower connecting plate, so that the movable side plate can be used as an axis at the lower end and its upper end can be moved between the upper connecting plate and the inner connecting plate The connecting plates are rotated left or right to change the inclination angle of the left and right side walls of the container; the bottom of the container is open, and a flexible bag is placed in the container, and the front and rear outer walls of the flexible bag are respectively pasted on the inner walls of the adjacent vertical plates, and the left and right outer walls of the flexible bag are respectively pasted on the inner walls of the two movable side plates, and the bottom of the flexible bag is exposed at the bottom of the container. When the flexible bag is opened, the container becomes a deformable container that can hold liquid and has variable inclination angles on the two side walls; the platform scale is placed below the container, and lifting screws are installed at the bottom of both ends of the bracket. The container can be raised and lowered by adjusting the lifting screws to adjust the gap between the container and the platform scale below, so that the gravity of the container wall is borne entirely by the dynamometer, and the platform scale only bears the liquid pressure transmitted by the upper flexible bag to measure the pressure of the liquid on the bottom of the container; by adjusting the inclination angles of the two side walls of the deformable container, the relationship between the pressure of the liquid on the bottom of the container and the shape of the container can be studied.
4. An experimental device for exploring the relationship between the pressure of liquid on the bottom of a container and the shape of the container as claimed in claim 3, characterized in that: The container is made of transparent material, and the flexible bag is a plastic bag or a rubber bag.