Centripetal force demonstration instrument

Abstract

The utility model relates to a centripetal force demonstration instrument, which comprises a base, a turntable and a hollow triangular prism assembled at the center of the top of the turntable, the top of the base is provided with a groove, a motor is mounted in the groove, and the center of the bottom of the turntable is mounted on an output shaft of the motor; tension sensors are installed at the bottom ends of the three side edges of the hollow triangular prism, an ESP32 plate and a 5v battery used for supplying power to the plate are further installed in the hollow triangular prism, the battery is used for supplying power to the tension sensors, and penetrating holes are formed in the bottoms of the tension sensors. When the motor drives the rotating disc and the hollow triangular prism to rotate, the pull rope pulls the rotating weight to rotate along with the rotating disc and provides centripetal force for the rotating weight, and at the moment, the tension sensor can measure the magnitude of the corresponding centripetal force and is convenient to check.

Description

Technical Field

[0001] The present application relates to the technical field of teaching aids, and in particular to a centripetal force demonstration apparatus. Background Art

[0002] Physics is a subject based on experiments. Experimental teaching is an extremely important part of the physics teaching process, and experimental instruments are auxiliary devices for physics teaching. For example, the traditional centripetal force experimental device is to turn the handle, which can make the speed change tower wheels A and B, long slots C and short slots D rotate accordingly, and the small balls in the slots also move in a circular motion. The centripetal force that makes the small balls move in a circular motion is provided by the pressure of the baffle of the cross arm on the small balls. The reaction force of the ball on the baffle, through the lever action of the cross arm, causes the spring force measuring sleeve to drop, thereby exposing the scale. According to the red and white equal division marks exposed on the scale, the ratio of the centripetal forces on the two balls can be roughly calculated.

[0003] However, in actual applications, the above experimental device has some defects. For example, when exploring the relationship between the centripetal force and the rotation speed, uniform rotation is required. However, the rotation of this device is driven by a handle, and the experimenters know that it is impossible for the handle to rotate at a uniform speed. At the same time, there is a lot of friction between the sleeve and the spring, and the measurement results have large errors.

[0004] Therefore, those skilled in the art provide a centripetal force demonstration apparatus to solve the problems raised in the above background technology. Utility Model Content

[0005] In order to solve the problems raised in the above background technology, the present application provides a centripetal force demonstration instrument.

[0006] The centripetal force demonstration device provided in this application adopts the following technical solution:

[0007] The centripetal force demonstrator comprises a base, a turntable and a hollow triangular prism mounted at the top center of the turntable, wherein a groove is dug at the top of the base, and a motor is installed in the groove, and the bottom center of the turntable is installed on the output shaft of the motor;

[0008] Tension sensors are installed on the bottom ends of the three sides of the hollow triangular prism. An ESP32 board and a 5V battery for powering the board are also installed inside the hollow triangular prism. The battery is used to power the tension sensor. A perforation is provided at the bottom of the tension sensor, and a stainless steel butterfly buckle is installed on the perforation outlet. A pull rope is passed through the perforation, and a rotating weight is bolted to the outer end of the pull rope.

[0009] Furthermore, a carrier plate is installed in the top opening of the hollow triangular prism, the top ends of the three pull ropes are all passed through the carrier plate, and the top ends of the pull ropes are bolted with pull rings.

[0010] Furthermore, a screw is mounted on the top of the tension sensor, and the screw is threadedly connected to the side of the hollow triangular prism.

[0011] Furthermore, a pedestal is provided on one side of the base, and a photoelectric gate is installed on the top of the pedestal, and a light shielding sheet cooperating with the photoelectric gate is also provided at the edge of the turntable.

[0012] Furthermore, the top end of the light shielding sheet is bent and fitted on the top of the turntable and fixed on the turntable by screws. The top surface of the turntable is also marked with scale lines along the radial direction.

[0013] In summary, this application includes the following beneficial technical effects:

[0014] 1. In this application, a motor is installed on the base, and the output shaft of the motor is connected to the bottom center of the turntable. The turntable is driven by the motor to rotate, which is convenient for keeping the turntable rotating at a constant speed, can be accurately controlled, and the speed regulation is relatively convenient, and the experimental data is more accurate.

[0015] 2. In this application, when the motor drives the turntable and the hollow triangular prism to rotate, the pull rope will pull the rotating weight to rotate along with the turntable and provide centripetal force for the rotating weight. At this time, the tension sensor can measure the size of the corresponding centripetal force for easy viewing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of this application;

[0017] Figure 2 It is a schematic diagram of the structure after the base is separated in this application.

[0018] Explanation of the reference numerals: 1. base; 11. motor; 2. turntable; 21. light shield; 22. scale line; 23. photoelectric gate; 24. pedestal; 3. hollow triangular prism; 31. tension sensor; 32. stainless steel butterfly buckle; 33. pull rope; 34. rotating weight; 35. screw; 36. carrier plate; 37. pull ring. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] Embodiment 1

[0021] Reference Figure 1 , Figure 2As shown, the present application discloses a centripetal force demonstrator, comprising a base 1, a turntable 2 and a hollow triangular prism 3 mounted at the top center of the turntable 2, the top surface of the turntable 2 is marked with scale lines 22 along the radial direction, a groove is dug at the top of the base 1, and a motor 11 is installed in the groove, and the bottom center of the turntable 2 is mounted on the output shaft of the motor 11;

[0022] Specifically, a motor 11 is installed on the base 1, and the output shaft of the motor 11 is connected to the bottom center of the turntable 2. The turntable 2 is driven to rotate by the motor 11, which is convenient for keeping the turntable 2 rotating at a constant speed, can be accurately controlled, and the speed regulation is relatively convenient, and the experimental data is more accurate.

[0023] Tension sensors 31 are installed on the bottom ends of the three sides of the hollow triangular prism 3. The top of the tension sensor 31 is also equipped with a screw 35. The screw 35 is threadedly connected to the side of the hollow triangular prism 3. An ESP32 board and a 5V battery for powering the board are also installed inside the hollow triangular prism 3. The battery is used to power the tension sensor 31. A perforation is set at the bottom of the tension sensor 31, and a stainless steel butterfly buckle 32 is installed on the perforation outlet. A pull rope 33 is passed through the perforation, and a rotating weight 34 is bolted to the outer end of the pull rope 33.

[0024] In addition, a hollow triangular prism 3 is provided on the turntable 2. When the motor 11 drives the turntable 2 and the hollow triangular prism 3 to rotate, the pull rope 33 will pull the rotating weight 34 to rotate with the turntable 2 and provide centripetal force for the rotating weight 34. At this time, the tension sensor 31 can measure the size of the corresponding centripetal force, and can transmit it to the phyphox software on the mobile phone in real time through the Bluetooth module of the ESP32 board for easy viewing.

[0025] Reference Figure 1 , Figure 2 As shown, a carrier plate 36 is also installed in the top opening of the hollow triangular prism 3, and the top ends of the three pull ropes 33 are all passed through the carrier plate 36, and a pull ring 37 is bolted to the top end of the pull rope 33. In order to adjust the length of the pull rope 33, when the pull ring 37 is pulled, the rotating weight 34 can be pulled close to the hollow triangular prism 3 to adjust the length, and the pull rope 33 can be locked by the stainless steel butterfly buckle 32.

[0026] Reference Figure 1 , Figure 2 As shown, a pedestal 24 is provided on one side of the base 1, and a photoelectric gate 23 is installed on the top of the pedestal 24. A light blocking sheet 21 cooperating with the photoelectric gate 23 is also provided at the edge of the turntable 2. The top end of the light blocking sheet 21 is bent and fits on the top of the turntable 2 and is fixed to the turntable 2 by screws. The light blocking sheet 21 is installed on the edge of the turntable 2. When the turntable 2 rotates, the light blocking sheet 21 will follow the rotation and pass through the photoelectric gate 23. At this time, the rotation speed of the turntable 2 can be measured.

[0027] Objects of different masses are placed on different radii of the turntable 2, and the motor 11 is adjusted from slow to fast. Different objects are thrown out of the turntable 2 as it rotates faster and faster. At this time, students are guided to make conjectures: 1. The magnitude of the centripetal force when an object makes circular motion may be related to the radius of the object's circular motion; 2. The magnitude of the centripetal force when an object makes circular motion may be related to the mass of the object; 3. The magnitude of the centripetal force when an object makes circular motion may be related to the rotation speed. In the process of reminding students to observe phenomena and then guiding them to make conjectures, students' scientific thinking is cultivated and improved.

[0028] Embodiment 2

[0029] To explore the relationship between the centripetal force and the radius, it is necessary to control the rotational speed of the rotating weight 34 and the turntable 2 to remain unchanged, change the length of the pull rope 33, first control the stainless steel butterfly buckle 32 to release the pull rope 33 of a suitable length, so that the three tension sensors 31 release the pull ropes 33 of different lengths, so that three sets of data can be obtained by doing one experiment. Through the above experiment, the relationship between the centripetal force and the radius is obtained. Repeat the above experimental steps to obtain a series of experimental data, and the data table is as follows:

[0030] Explore the relationship between centripetal force and radius

[0031]

[0032] When exploring the relationship between the centripetal force and the mass of the rotating weight 34, it is necessary to control the length of the pull rope 33 and the speed of the turntable 2 to remain unchanged. When doing the experiment, control the stainless steel butterfly buckle 32 to release the pull rope 33 of appropriate length to ensure that the lines released by the three tension sensors 31 are the same length, that is, to ensure that the radius is the same. The rotating weight 34 hanging at the end of the line has different masses. Adjust the number of revolutions of the stepless motor 4 and start recording data after the speed stabilizes. Through the above experiments, three sets of data on the relationship between different masses and centripetal force can be obtained by doing one experiment. Repeat the above experimental steps to obtain a series of experimental data, and the data table is as follows:

[0033] Explore the relationship between centripetal force and mass

[0034]

[0035] When exploring the relationship between the centripetal force and the rotation speed of the turntable 2, it is necessary to control the length of the pull rope 33 and the mass of the rotating weight 34 to remain unchanged. When doing the experiment, control the stainless steel butterfly buckle 32 to release the pull rope 33 of appropriate length, ensure that the pull ropes 33 released by the three tension sensors 31 are the same length, that is, ensure that the radius is the same, and hang the rotating weight 34 of the same mass at the end of the line. Then, according to the needs of the experiment, adjust the motor 11 to different speeds. Each time you adjust the speed to a certain experimental speed, wait until the speed stabilizes before starting to record data. Repeat the above time steps to obtain a series of experimental data, and the data table is as follows:

[0036] Explore the relationship between centripetal force and rotation speed

[0037]

[0038] Embodiment 3

[0039] This centripetal force demonstrator has three tension sensors 31. Three sets of data can be collected at the same time in one experiment. Because they are on a turntable 2, the rotation speeds of the three tension sensors 31 are the same. The mass of the rotating weight 34 and the length of the pull rope 33 hung on each tension sensor 31 can be changed exponentially to explore whether the centripetal force increases exponentially with the exponential increase of the radius and mass. The measured data table is as follows:

[0040] At the same time, explore the relationship between the centripetal force and radius, mass and rotation speed

[0041]

[0042] The standard parts used in the utility model can all be purchased from the market, and special-shaped parts can be customized according to the instructions and the drawings. The specific connection methods of each part adopt mature conventional means such as bolts, rivets, welding, etc. in the existing technology. The machinery, parts and equipment all adopt conventional models in the existing technology, and the circuit connection adopts the conventional connection method in the existing technology, which will not be described in detail here.

[0043] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0044] The implementation principle of the centripetal force demonstration device of this application is:

[0045] When in use, according to the experimental requirements, first loosen the stainless steel butterfly buckle 32 and pull the pull ring 37. At this time, the pull rope 33 can slide, pull the rotating weight 34 to slide on the turntable 2, adjust the position of the rotating weight 34, and then re-lock the pull rope 33 through the stainless steel butterfly buckle 32 to ensure safety, and then start the motor 11 to measure data;

[0046] The turntable 2 is installed on the output shaft of the motor 11. The motor 11 drives the turntable 2 to rotate, which is convenient for keeping the turntable 2 rotating at a constant speed, can be accurately controlled, and the speed regulation is relatively convenient, and the experimental data is more accurate. When the motor 11 drives the turntable 2 and the hollow triangular prism 3 to rotate, the pull rope 33 will pull the rotating weight 34 to rotate with the turntable 2 and provide centripetal force for the rotating weight 34. At this time, the tension sensor 31 can measure the size of the corresponding centripetal force, and can be transmitted to the phyphox software on the mobile phone in real time through the Bluetooth module of the ESP32 board for easy viewing. In order to measure the rotation speed of the turntable 2, a light shielding sheet 21 is also installed on the edge of the turntable 2. When the light shielding sheet 21 rotates with the turntable 2, it will pass through the photoelectric gate 23, and the rotation speed of the turntable 2 can be measured at this time;

[0047] Measure the centripetal force required for the hook to move in a circular motion, marked as F 示 , and then through the centripetal force formula F 理论 =mω 2 r can be used to calculate the theoretical value of the required centripetal force, where m is the mass of the hook, ω is the angle element during the rotation of the turntable, measured by the photoelectric gate, and r is the radius of the hook's circular motion, which can be read directly from the scale line 22 on the turntable 2. By comparing F 示 and F 理论 The size relationship determines the accuracy of the experiment.

[0048] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A centripetal force demonstrator, comprising a base (1), a turntable (2), and a hollow triangular prism (3) mounted at the top center of the turntable (2), characterized in that: The top of the base (1) is provided with a groove, and a motor (11) is installed in the groove, and the bottom center of the turntable (2) is installed on the output shaft of the motor (11); Tension sensors (31) are installed on the bottom ends of the three sides of the hollow triangular prism (3). An ESP32 board and a 5V battery for powering the board are also installed inside the hollow triangular prism (3). The battery is used to power the tension sensor (31). A perforation is provided at the bottom of the tension sensor (31), and a stainless steel butterfly buckle (32) is installed on the outlet of the perforation. A pull rope (33) is inserted into the perforation, and a rotating weight (34) is bolted to the outer end of the pull rope (33).

2. The centripetal force demonstration device according to claim 1, characterized in that: A carrier plate (36) is also installed in the top opening of the hollow triangular prism (3), the top ends of the three pull ropes (33) are all passed through the carrier plate (36), and a pull ring (37) is bolted to the top end of the pull rope (33).

3. The centripetal force demonstration device according to claim 1, characterized in that: The top end of the tension sensor (31) is also equipped with a screw (35), which is threadedly connected to the side of the hollow triangular prism (3).

4. The centripetal force demonstration device according to claim 1, characterized in that: A pedestal (24) is also provided on one side of the base (1), and a photoelectric gate (23) is installed on the top of the pedestal (24). A light shielding sheet (21) cooperating with the photoelectric gate (23) is also provided at the edge of the turntable (2).

5. The centripetal force demonstration device according to claim 4, characterized in that: The top end of the light shielding sheet (21) is bent and fitted on the top of the turntable (2) and fixed on the turntable (2) by screws. The top surface of the turntable (2) is also marked with scale lines (22) along the radial direction.

Images