Teaching appliance for demonstrating transverse wave to pass through slit

Abstract

The invention, which relates to the technical field of the teaching appliance, discloses a teaching appliance for demonstrating the penetration of a transverse wave through a slit, comprising a top plate, a driving motor assembly, a rocker arm assembly, a woven cotton rope, a slit, a slit tray assembly, a guide seat, a guide seat tray, a base and a supporting column. Wherein the top plate, the slit tray assembly, the guide seat tray and the base are sequentially and fixedly connected in a penetrating mode through the supporting column from top to bottom, the driving motor assembly and the rocker arm assembly are fixedly connected to the top plate, the slit is installed on the slit tray assembly and has three selectable installation directions, the upper end of the woven cotton rope is fixed to the driving motor assembly, and the lower end of the woven cotton rope is fixed to the rocker arm assembly. And the lower end of the steel wire rope sequentially penetrates through the slit and the guide seat from top to bottom and then is knotted and mounted on the guide seat capable of adjusting three directions. The woven cotton rope vibrates to form stable transverse waves by starting the driving motor assembly, the change of the amplitude and the vibration direction of the transverse waves penetrating through the slit can be demonstrated by adjusting the direction of the slit, and students can establish physical models of light waves vibrating in different directions penetrating through the polaroid in an analogy mode.

Description

Technical Field

[0001] The invention relates to the technical field of teaching tools, in particular to a teaching tool for demonstrating transverse waves passing through slits. Background Art

[0002] Physics experiment teaching aids are tools specifically used to assist physics teaching. They are diverse and practical, and are designed to help students better understand physical models and thus master physical concepts and laws.

[0003] In the study of the "Polarization of Light" section in high school physics, students often cannot accurately understand the amplitude loss and change of vibration direction of light waves with different vibration directions after passing through the polarizer in the physics experiment of "Exploring whether light is a transverse wave or a longitudinal wave". Teachers need to first use the "Mechanical wave passing through a slit" experiment to provide students with a model basis, among which the "transverse wave passing through a slit" demonstration experiment is particularly important.

[0004] For the demonstration of the experiment of "transverse wave passing through a slit", the existing teaching aids have the following deficiencies:

[0005] 1. It can only demonstrate the situation when the vibration direction of the transverse wave is consistent with or perpendicular to the slit direction, but cannot demonstrate the situation when the vibration direction of the transverse wave is at a general angle to the slit direction.

[0006] 2. Some experimental schemes will form standing waves during demonstration, which is an obvious experimental interference factor.

[0007] 3. Some experimental schemes require teachers to manually drive the rope wave and demonstrate it on a large horizontal table, which is inconvenient to move and inconvenient for teachers to demonstrate and students to observe.

[0008] 4. There is no complete set of special experimental equipment. Summary of the invention

[0009] The invention provides a teaching tool for demonstrating transverse waves passing through slits, which has a stable wave source, a variable slit direction and is convenient for demonstration and observation.

[0010] A teaching tool for demonstrating transverse waves passing through a slit, characterized in that: it includes a top plate, the top plate is fixedly connected to the top ends of four supporting columns, a driving motor assembly and a rocker assembly are fixedly installed vertically downward on the top plate, the driving motor assembly and the rocker assembly are clearance-matched, the rocker assembly is fixedly connected to the upper end of a braided cotton rope, the braided cotton rope passes vertically downward through the slit, the slit is installed on a slit tray assembly, the slit tray assembly has three groups of slit mounting grooves, the slit tray assembly is fixedly connected to the supporting columns, and the slit tray assembly is located between the supporting columns. In the middle position in the vertical direction, the support column is fixedly connected downwardly to the guide seat tray, there are 3 groups of guide seat mounting grooves on the guide seat tray, the guide seat tray is 50mm away from the lower end of the support column, a guide seat is installed on the guide seat tray, a guide groove is opened in the center of the guide seat, two wedge-shaped claws are symmetrically fixedly installed at both ends of the guide groove, the wedge-shaped claws are clearance-matched with the guide seat mounting groove, the lower end of the braided cotton rope passes through the guide groove and is knotted to form a knot, the knot cannot pass through the guide groove upward, and the lower end of the support column is fixedly connected to the base.

[0011] Furthermore, the rocker arm assembly includes a rocker arm base, which is fixedly connected to the top plate, and a bushing is installed downwardly on the rocker arm base through the rocker arm shaft, and the axial clearance between the bushing and the rocker arm base is in the range of 0.05~0.1mm, and the radial clearance between the bushing and the rocker arm shaft is in the range of 0.05~0.1mm, and the bushing is fixedly connected to the rocker arm, and there is a rocker arm slot in the center of the rocker arm, and first and second rocker arm holes of equal size are symmetrically distributed at both ends of the rocker arm, and the first rocker arm hole is used to install the braided cotton rope, and the second rocker arm hole is used to be fixedly connected to the bushing, and the rocker arm can swing around the rocker arm shaft.

[0012] Furthermore, the drive motor assembly includes a drive motor, the drive motor is fixedly connected to a drive crank, the drive crank is fixedly connected to a drive rod, the drive rod and the rocker arm slide groove have a clearance fit, and the fit clearance is in the range of 0.1~0.15mm.

[0013] Furthermore, the slit tray assembly includes a slit tray, a first center clearance hole is provided at the center of the slit tray, three groups of slit mounting grooves are distributed counterclockwise in the circumferential direction of the first center clearance hole, each group of the slit mounting grooves includes two slit mounting grooves, and the two slit mounting grooves are centrally symmetrically distributed about the center of the first center clearance hole, and the angle between two adjacent groups of the slit mounting grooves is 45°, and the gap between the slits and the slit mounting grooves is matched, and the gap is in the range of 0.1~0.2mm.

[0014] Furthermore, the slit width is within the range of 6 to 7 mm, and the slit length should be ensured to be no less than the amplitude of the braided cotton rope during operation.

[0015] Furthermore, the braided cotton rope is cylindrical in shape, with a diameter smaller than the width of the slit by about 1 mm. After being connected to the rocker arm assembly, it is in a freely hanging state and is coplanar with the swing plane of the rocker arm.

[0016] Furthermore, there is a second center clearance hole in the center of the guide seat tray, and three groups of guide seat mounting grooves are distributed counterclockwise along the circumferential direction of the second center clearance hole, each group of the guide seat mounting grooves includes two guide seat mounting grooves, and the two guide seat mounting grooves are distributed in a centrally symmetrical manner about the center of the second center clearance hole, and the angle between two adjacent groups of guide seat mounting grooves is 45°.

[0017] Furthermore, the width of the guide groove is consistent with the width of the slit, the length of the guide groove should be ensured to be no less than the amplitude of the braided cotton rope, and the installation direction of the guide groove should be ensured to be consistent with the installation direction of the slit.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. When the present invention is used, there is no need for the teacher to manually drive the shear wave, and stable shear waves can be generated by starting the driving motor.

[0020] 2. The transverse waves generated by the present invention when in use have good polarization, that is, the vibration of the braided cotton rope is in a fixed vertical plane.

[0021] 3. When the present invention is used, the teacher can adjust the angle between the slit direction and the transverse wave vibration direction, so that students can observe the loss of amplitude and the change of vibration direction of the transverse wave after passing through the slit when the angle between the two is at different angles.

[0022] 4. The experimental device is easy to move, which is convenient for teachers to demonstrate and students to observe.

[0023] In summary, the present invention enables teachers to demonstrate the "transverse wave passing through a slit" experiment by only changing the installation direction of the slit to allow students to observe the changes in amplitude and vibration direction of the transverse wave before and after passing through slits in different directions. The experiment is simple to operate, the experimental phenomena are obvious and intuitive, and it is conducive to teacher demonstration and student observation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0025] Figure 2 It is a schematic diagram of the structure of the slit tray assembly of the present invention.

[0026] Figure 3 It is a structural schematic diagram of the guide seat of the present invention.

[0027] Figure 4 It is a structural schematic diagram of the guide seat tray of the present invention.

[0028] Figure 5 It is a schematic diagram of assembling the guide seat and the guide seat tray of the present invention.

[0029] Figure 6 It is a schematic diagram of assembling the braided cotton rope and the guide seat of the present invention.

[0030] Figure 7 It is a schematic diagram of the slit structure of the present invention.

[0031] Figure 8 It is a schematic diagram of the structure of the rocker arm assembly of the present invention.

[0032] Fig. 9 It is a schematic diagram of the rocker arm structure of the present invention.

[0033] Fig.10 It is a schematic diagram of the structure of the drive motor assembly of the present invention.

[0034] Fig.11 It is a schematic diagram of the assembly of the drive motor assembly and the rocker arm assembly of the present invention.

[0035] Explanation of the accompanying drawings: 1_top plate, 2_slit tray assembly, 201_slit tray, 202_slit mounting groove, 203_first center clearance hole, 3_guide seat, 301_guide groove, 302_wedge-shaped claw, 4_guide seat tray, 401_guide seat mounting groove, 402_second center clearance hole, 5_base, 6_support column, 7_braided cotton rope, 701_knot, 8_slit, 9_rocker arm assembly, 901_rocker arm base, 902_bushing, 903_rocker arm, 9031_first rocker arm hole, 9032_rocker arm slide groove, 9033_second rocker arm hole, 904_rocker arm shaft, 10_drive motor assembly, 1001_drive motor, 1002_drive crank, 1003_drive rod. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Embodiment 1: A teaching aid for demonstrating transverse wave passing through a slit, combined with the attached Figure 1 To Attachment Fig.11, including a top plate 1, the top plate 1 is fixedly connected to the top ends of four supporting columns 6, the top plate 1 is vertically fixedly installed with a driving motor assembly 10 and a rocker assembly 9, the driving motor assembly 10 and the rocker assembly 9 are clearance-matched, the rocker assembly 9 is fixedly connected to the upper end of a braided cotton rope 7, the braided cotton rope 7 passes through a slit 8 vertically downward, the slit 8 is installed on a slit tray assembly 2, the slit tray assembly 2 has three groups of slit mounting grooves 202, the slit tray assembly 2 is fixedly connected to the supporting column 6, the slit tray assembly 2 is in the middle position of the supporting column 6 in the vertical direction, the supporting column 6 is downwardly fixedly connected to a guide seat tray 4, the guide seat tray 4 has three groups of guide seat mounting grooves 401, and the guide seat tray 4 is 1.5 meters away from the guide seat tray 4. The lower end of the supporting column 6 is 50mm, and the guide seat 3 is installed on the guide seat tray 4. The center of the guide seat 3 has a guide groove 301. Two wedge-shaped claws 302 are symmetrically fixedly installed at both ends of the guide groove 301. The wedge-shaped claws 302 are clearance-matched with the guide seat installation groove 401. The lower end of the braided cotton rope 7 passes through the guide groove 301 and is knotted to form a knot 701. The knot 701 cannot pass through the guide groove 301 upward. The length of the braided cotton rope 7 should ensure that the lower end exceeds the guide groove 301 of the guide seat 3 by about 150mm when it is freely drooping after correct installation. The lower end of the supporting column 6 is fixedly connected to the base 5. After the installation is completed, the top plate 1, the slit tray assembly 2, the guide seat tray 4 and the base 5 should be parallel to each other.

[0038] Combined with Figure 8 and attached Fig. 9 The rocker arm assembly 9 includes a rocker arm base 901, which is fixedly connected to the top plate 1. A bushing 902 is installed downwardly on the rocker arm base 901 through the rocker arm shaft 904. The axial clearance between the bushing 902 and the rocker arm base 901 is in the range of 0.05~0.1mm, and the radial clearance between the bushing 902 and the rocker arm shaft 904 is in the range of 0.05~0.1mm. The bushing 902 is fixedly connected to the rocker arm 903. There is a rocker arm slide groove 9032 in the center of the rocker arm 903. The first rocker arm hole 9031 and the second rocker arm hole 9033 of equal size are symmetrically distributed at both ends of the rocker arm 903. The first rocker arm hole 9031 is used to install the braided cotton rope 7, and the second rocker arm hole 9033 is used to be fixedly connected to the bushing 902. The rocker arm 903 can swing around the rocker arm shaft 904.

[0039] Combined with Fig. 9 , attached Fig.10 and attached Fig.11 The drive motor assembly 10 includes a drive motor 1001, which is fixedly connected to a drive crank 1002, and the drive crank 1002 is fixedly connected to a drive rod 1003. The drive rod 1003 and the rocker arm slide groove 9032 have a clearance fit, and the clearance is in the range of 0.1 to 0.15 mm.

[0040] Combined with Figure 2The slit tray assembly 2 includes a slit tray 201, a first center clearance hole 203 is provided at the center of the slit tray 201, three groups of slit mounting grooves 202 are distributed counterclockwise in the circumferential direction of the first center clearance hole 203, each group of slit mounting grooves includes two slit mounting grooves 202, and the two slit mounting grooves 202 are centrally symmetrically distributed about the center of the first center clearance hole 203, and the angle between two adjacent groups of slit mounting grooves 202 is 45°, and the gap between the slit 8 and the slit mounting groove 202 is matched, and the gap is in the range of 0.1~0.2mm.

[0041] Combined with Figure 4 There is a second center clearance hole 402 in the center of the guide seat tray 4, and three groups of guide seat mounting grooves 401 are distributed counterclockwise along the circumferential direction of the second center clearance hole 402, each group includes two guide seat mounting grooves 401, and the two guide seat mounting grooves 401 are centrally symmetrically distributed about the center of the second center clearance hole 402, and the angle between two adjacent groups of guide seat mounting grooves 401 is 45°.

[0042] Before using this device to demonstrate the experiment, the teacher should first ensure that the braided cotton rope 7 is in the swing plane of the rocker arm 903 when it is hanging freely, install the slit 8 in the first group of slit mounting grooves 202, and after installation, the direction of the slit 8 is coplanar with the swing plane of the rocker arm 903, and the wedge-shaped claw 302 on the guide seat 3 is inserted into the first group of guide seat mounting grooves 401 to ensure that the direction of the guide groove 301 is consistent with the direction of the slit 8.

[0043] When the teacher uses this device, he starts the driving motor 1001, and the driving motor 1001 can drive the driving crank 1002 and the driving rod 1003 to rotate at a uniform speed. When the driving rod 1003 rotates, it slides in the rocker arm slot 9032 and drives the rocker arm 903 to swing back and forth within a fixed angle range, thereby driving the upper end of the braided cotton rope 7 to vibrate to form a stable wave source. The vibration propagates downward along the braided cotton rope 7 to form a stable transverse wave, and the transverse wave can smoothly pass through the slit 8. After the transverse wave passes through the slit 8, the amplitude is not lost and the vibration direction does not change.

[0044] Subsequently, the slit 8 is removed from the first group of slit mounting grooves 202, rotated 45° counterclockwise and installed in the adjacent second group of slit mounting grooves 202. At the same time, the guide seat 3 is removed from the first group of guide seat mounting grooves 401, rotated 45° counterclockwise and installed in the adjacent second group of guide seat mounting grooves 401. At this time, the direction of the slit 8 forms an angle of 45° with the vibration direction of the transverse wave before passing through the slit 8. It can be observed that the vibration direction of the transverse wave deviates from the original vibration direction after passing through the slit 8, becomes consistent with the direction of the slit 8, and the amplitude is attenuated.

[0045] Next, the slit 8 is removed from the second group of slit mounting grooves 202 again, rotated 45° counterclockwise and installed in the adjacent third group of slit mounting grooves 202. At the same time, the guide seat 3 is removed from the second group of guide seat mounting grooves 401, rotated 45° counterclockwise and installed in the adjacent third group of guide seat mounting grooves 401. At this time, the direction of the slit 8 is perpendicular to the vibration direction of the transverse wave before passing through the slit 8. It can be observed that the transverse wave cannot continue to propagate through the slit 8.

[0046] In summary, the present invention enables teachers to present to students the obvious and intuitive experimental phenomenon of transverse waves passing through slits in different directions simply by adjusting the installation directions of the slit 8 and the guide seat 3 after starting the drive motor 1001 when demonstrating the experiment of "transverse waves passing through slits". This is conducive to students building a correct physical model of "transverse waves passing through slits", and is conducive to students building a physical model of light waves vibrating in different directions passing through polarizers by analogy, and is conducive to developing students' core physical literacy.

Claims

1. A teaching tool for demonstrating transverse waves passing through slits, characterized in that: The invention comprises a top plate (1), wherein the top plate (1) is fixedly connected to the top ends of four supporting columns (6), a driving motor assembly (10) and a rocker arm assembly (9) are fixedly installed on the top plate (1) vertically downward, the driving motor assembly (10) and the rocker arm assembly (9) are clearance-matched, the rocker arm assembly (9) is fixedly connected to the upper end of a braided cotton rope (7), the braided cotton rope (7) passes through a slit (8) vertically downward, the slit (8) is installed on a slit tray assembly (2), the slit tray assembly (2) has three groups of slit installation grooves (202), the slit tray assembly (2) is fixedly connected to the supporting columns (6), the slit tray assembly (2) is located in the middle position of the supporting columns (6) in the vertical direction, and the supporting columns (6) are downward. The guide seat tray (4) is fixedly connected to the guide seat tray (4), the guide seat tray (4) has three groups of guide seat installation grooves (401), the guide seat tray (4) is 50 mm away from the lower end of the support column (6), the guide seat tray (4) is installed with a guide seat (3), the center of the guide seat (3) has a guide groove (301), two wedge-shaped claws (302) are symmetrically fixedly installed at both ends of the guide groove (301), the wedge-shaped claws (302) are clearance-matched with the guide seat installation groove (401), the lower end of the braided cotton rope (7) passes through the guide groove (301) and is tied to form a knot (701), the knot (701) cannot pass through the guide groove (301) upwards, and the lower end of the support column (6) is fixedly connected to the base (5).

2. A teaching tool for demonstrating transverse wave passing through a slit according to claim 1, characterized in that: The rocker arm assembly (9) comprises a rocker arm base (901), the rocker arm base (901) being fixedly connected to the top plate (1), a bushing (902) being installed downwardly on the rocker arm base (901) through a rocker arm rotating shaft (904), an axial clearance between the bushing (902) and the rocker arm base (901) being in the range of 0.05 to 0.1 mm, a radial clearance between the bushing (902) and the rocker arm rotating shaft (904) being in the range of 0.05 to 0.1 mm, the bushing (902) being fixedly connected to a rocker arm (903), a rocker arm slide groove (9032) being provided at the center of the rocker arm (903), and a first rocker arm hole (9031) and a second rocker arm hole (9033) of equal size being symmetrically distributed at both ends of the rocker arm (903).

3. A teaching tool for demonstrating transverse wave passing through a slit according to claim 1 or 2, characterized in that: The drive motor assembly (10) comprises a drive motor (1001), wherein the drive motor (1001) is fixedly connected to a drive crank (1002), wherein the drive crank (1002) is fixedly connected to a drive rod (1003), and wherein the drive rod (1003) and the rocker arm slide groove (9032) are clearance-matched, and the clearance is within a range of 0.1 to 0.15 mm.

4. The teaching tool for demonstrating transverse wave passing through a slit according to claim 1, characterized in that: The slit tray assembly (2) comprises a slit tray (201), the center of the slit tray (201) having a first central clearance hole (203), three groups of slit mounting grooves (202) distributed counterclockwise in the circumferential direction of the first central clearance hole (203), each group of the slit mounting grooves (202) comprising two slit mounting grooves (202), the two slit mounting grooves (202) being centrally symmetrically distributed about the center of the first central clearance hole (203), the angle between two adjacent groups of the slit mounting grooves (202) being 45°, and the gap between the slit (8) and the slit mounting groove (202) being matched, the gap being in the range of 0.1-0.2 mm.

5. The teaching tool for demonstrating transverse wave passing through a slit according to claim 1, characterized in that: The guide seat tray (4) has a second central clearance hole (402) at its center, and three groups of guide seat mounting grooves (401) are distributed counterclockwise along the circumferential direction of the second central clearance hole (402), each group of the guide seat mounting grooves (401) includes two guide seat mounting grooves (401), and the two guide seat mounting grooves (401) are distributed in a centrally symmetrical manner about the center of the second central clearance hole (402), and the angle between two adjacent groups of the guide seat mounting grooves (401) is 45°.

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