CN112133169A - Centripetal force experiment device and radius calculation method for moving object to do uniform-speed circular motion - Google Patents
Centripetal force experiment device and radius calculation method for moving object to do uniform-speed circular motion Download PDFInfo
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- CN112133169A CN112133169A CN202011118466.3A CN202011118466A CN112133169A CN 112133169 A CN112133169 A CN 112133169A CN 202011118466 A CN202011118466 A CN 202011118466A CN 112133169 A CN112133169 A CN 112133169A
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- moving object
- centripetal force
- diffuse reflection
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
- G09B23/00—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes
- G09B23/06—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics
- G09B23/08—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for statics or dynamics
- G09B23/10—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for statics or dynamics of solid bodies
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/08—Measuring arrangements characterised by the use of optical techniques for measuring diameters
- G01B11/12—Measuring arrangements characterised by the use of optical techniques for measuring diameters internal diameters
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Abstract
The invention discloses a centripetal force experimental device, which comprises: the device comprises a turntable motor, a screw motor, a turntable, a sliding table, a resistance ruler, a moving object and a diffuse reflection laser sensor, wherein the turntable motor drives the turntable to do uniform circular motion; a screw rod of the screw rod motor drives the sliding table to move towards the center of the rotary table or move away from the center of the rotary table, and the screw rod motor is detachably and fixedly arranged on the rotary table; the transmission shaft of the resistance ruler is telescopically connected and fixed on the sliding table, and the resistance ruler is detachably and fixedly arranged on the rotary table; the invention also discloses a radius calculation method for the moving object to do uniform-speed circular motion, and the relation between centripetal force and influencing factors is researched.
Description
Technical Field
The invention relates to the technical field of teaching equipment, in particular to a centripetal force experimental device and a radius calculation method for a moving object to perform uniform-speed circular motion.
Background
The centripetal force problem is one of the important contents of the mechanics part in physics, and the important point is the relationship between the centripetal force applied to an object doing circular motion and the motion angular velocity, the motion linear velocity, the motion radius and the motion object mass. It is difficult for learners to understand and accept only by teacher explanation in teaching, and experimental support is necessary.
The existing centripetal force teaching experimental scheme and experimental device have a common defect that only the relation between the centripetal force and the angular velocity is researched, but the relation between the centripetal force and all influence factors cannot be researched.
In view of the above, the present inventors have made extensive studies and intensive studies to solve the above problems, and as a result, the present invention has been developed and designed.
Disclosure of Invention
The invention aims to provide a centripetal force experimental device which is simple in structure and convenient for researching the relation between the centripetal force and all influence factors.
In order to achieve the purpose, the solution of the invention is as follows:
a centripetal force testing device comprising: the device comprises a turntable motor, a screw motor, a turntable, a sliding table, a resistance ruler, a moving object and a diffuse reflection laser sensor, wherein the turntable motor drives the turntable to do uniform circular motion; a screw rod of the screw rod motor drives the sliding table to move towards the center of the rotary table or move away from the center of the rotary table, and the screw rod motor is detachably and fixedly arranged on the rotary table; the transmission shaft of the resistance ruler is telescopically connected and fixed on the sliding table, and the resistance ruler is detachably and fixedly arranged on the rotary table; and a stop block is convexly extended below the moving object, and when the moving object rotates for a circle, the opposite point on the central axis of the stop block can be opposite to the diffuse reflection laser sensor once.
The centripetal force experiment device further comprises a support, and the diffuse reflection laser sensor is detachably and fixedly arranged on the surface, facing the stop block, of the support.
The support is of an inverted L shape.
A polish rod is arranged on the sliding table in a penetrating mode, and a base of the polish rod is detachably and fixedly arranged on the rotary table.
An opening slide rail is detachably and fixedly arranged on the rotary table, the moving object is slidably arranged on the opening slide rail, the stop block penetrates through the middle of the opening slide rail, and the stop block is arranged below the rotary table.
The turntable is detachably and fixedly provided with a first limiting piece and a second limiting piece, and the sliding table is limited by the movement between the first limiting piece and the second limiting piece.
The utility model provides a centripetal force experimental apparatus, still includes the supporting seat, be equipped with total control circuit module on the supporting seat, the carousel motor sets firmly on the supporting seat, connect a foraminiferous adapter on the output shaft of carousel motor, be equipped with a conductive slip ring in the foraminiferous adapter, total control circuit module's connecting wire is around establishing to conductive slip ring to stretch out the hole of foraminiferous adapter, and be connected to carousel motor, lead screw motor, diffuse reflection laser sensor and resistance ruler.
The general control circuit module is provided with a speed regulation potentiometer, a screw rod motor control circuit module, a turntable motor control circuit module and an AD conversion circuit module, wherein the speed regulation potentiometer can regulate the speed of the turntable motor, the speed regulation potentiometer is electrically connected with the turntable motor control circuit module and the turntable motor, the screw rod motor control circuit module is electrically connected with the screw rod motor, and the diffuse reflection laser sensor and the resistance ruler are electrically connected with the AD conversion circuit module.
The moving object is a trolley.
The trolley is provided with a fixed rod, and weights are selectively arranged on the fixed rod.
A radius calculation method for a moving object to do uniform circular motion applies the centripetal force experiment device, the width of the stop block is equal to the displacement delta L of the moving object in delta t time, and the method comprises the following steps:
the method comprises the following steps: measuring delta t by using a diffuse reflection laser sensor, namely the time t when the front edge of the stop block is aligned to block the diffuse reflection laser sensor is t1The time for the rear edge of the stop block to face and block the diffuse reflection laser sensor is t2,t1、t2Measured by a diffuse reflection laser sensor, t ═ t2-t1；
Step two: calculating the time difference of the two diffuse reflection laser sensors in the opposite position on the central axis of the stop block by using the diffuse reflection laser sensors, namely the period T of the uniform circular motion of the moving object;
step three: calculating the rotating angle of the moving object in the time delta T according to the value alpha ═ delta T/T multiplied by 360;
step four: according to
And calculating the radius of the moving object in uniform circular motion.
After the technical scheme is adopted, according to the Newton's third motion law, the pressure sensor can measure the pressure of the moving object on the sliding table, the counter-acting force of the sliding table on the moving object provides the centripetal force for the moving object to perform uniform-speed circular motion, the centripetal force for the moving object to perform uniform-speed circular motion is equal to the pressure of the moving object on the sliding table, the resistance ruler can measure the radius of the moving object to perform uniform-speed circular motion, and the diffuse reflection laser sensor can measure the period of the moving object to perform uniform-speed circular motion, so that according to F ═ mr (2 pi/T)2The centripetal force of the moving object doing uniform circular motion can be calculated, and the centripetal force and the calculated centripetal force of the moving object doing uniform circular motion can be obtained by comparing the calculated centripetal force with the pressure of the moving object on the sliding tableThe relationship between the influencing factors facilitates the research of the relationship between the centripetal force and the influencing factors, and the structure of the invention is simple.
Drawings
Fig. 1 is a perspective view of the present invention.
Fig. 2 is a partial perspective view (1) of the present invention.
Fig. 3 is a partial perspective view (2) of the present invention.
[ notation ] to show
Turntable motor 1
Screw motor 2
Screw rod 21
Rotary table 3
Sliding table 4
Trolley 61 weight 62 stop 63 fixing rod 64
Front edge a and back edge b of contraposition point o on central axis
Diffuse reflection laser sensor 7
Support 8
First locating part 01 and second locating part 02
Supporting seat 03
Speed-regulating potentiometer 041
Lead screw motor control circuit module 042
Turntable motor control circuit module 043
AD conversion circuit module 044
Connecting line 05.
Detailed Description
To achieve the above objects and advantages, the present invention provides a novel and improved technical means and structure, which will be described in detail in connection with the preferred embodiments of the present invention.
Referring to fig. 1 to 3, the present invention discloses a centripetal force testing apparatus, comprising: the device comprises a turntable motor 1, a screw rod motor 2, a turntable 3, a sliding table 4, a resistance ruler 5, a moving object and a diffuse reflection laser sensor 7, wherein the turntable motor 1 drives the turntable 3 to do uniform circular motion, a pressure sensor 41 is arranged on the surface of the sliding table 4 facing the circle center of the turntable 3, the moving object abuts against the pressure sensor 41, and the moving object does uniform circular motion along with the turntable 3; the screw rod 21 of the screw rod motor 2 drives the sliding table 4 to move towards the circle center of the rotary table 3 or move away from the circle center of the rotary table 3, and the screw rod motor 2 is detachably and fixedly arranged on the rotary table 3; the transmission shaft 51 of the resistance ruler 5 is telescopically connected and fixed on the sliding table 4, and the resistance ruler 5 is detachably and fixedly arranged on the rotary table 3; a stop block 63 protrudes and extends below the moving object, and when the moving object rotates for a circle, a contraposition point o on the central axis of the stop block 63 can be positioned on the diffuse reflection laser sensor 7 once; the lead screw 21 of the lead screw motor 2 is arranged in parallel with the transmission shaft 51 of the resistance ruler 5 at intervals; the pressure sensor 41 may be a film pressure sensor.
Therefore, according to the present invention, through the turntable motor 1, the lead screw motor 2, the turntable 3, the sliding table 4, the resistive ruler 5, the moving object and the diffuse reflection laser sensor 7, according to the newton's third motion law, the pressure of the moving object on the sliding table 4 can be measured by the pressure sensor 41, the centripetal force of the moving object on the sliding table 4 at the uniform speed circular motion is provided by the reaction force of the sliding table 4 on the moving object, the centripetal force of the moving object on the uniform speed circular motion is equal to the pressure of the moving object on the sliding table 4, the radius of the moving object on the uniform speed circular motion can be measured by the resistive ruler 5, and the period of the moving object on the uniform speed circular motion can be measured by the diffuse reflection laser sensor 7, such that according2The centripetal force of the moving object doing uniform circular motion can be calculated, the relationship between the centripetal force and all the influence factors can be obtained by comparing the calculated centripetal force of the moving object doing uniform circular motion with the pressure of the moving object on the sliding table 4, the relationship between the centripetal force and the influence factors can be conveniently researched, and the structure of the invention is simple; the diffuse reflection laser sensor 7 can also measure the linear velocity of the moving object making uniform circular motion, and can also be based on
The centripetal force of the moving object doing the uniform circular motion is calculated, the calculated centripetal force of the moving object doing the uniform circular motion may have an error with the pressure of the moving object on the sliding table 4, but data within the error range can also indicate that the calculated centripetal force of the moving object doing the uniform circular motion is equal to the pressure of the moving object on the sliding table 4, and the output data (namely the voltage value of the moving end) measured by the resistance ruler is in a linear relation with the linear motion distance, so that the radius of the moving object doing the uniform circular motion can be measured.
Furthermore, in order to facilitate fixing the diffuse reflection laser sensor 7, the diffuse reflection laser sensor 7 may further include a bracket 8, and the diffuse reflection laser sensor 7 may be detachably fixed on a surface of the bracket 8 facing the stopper 63.
Then, the sliding table 4 can be provided with a polished rod 9 with a balance function in a penetrating way, and the base 91 of the polished rod is detachably and fixedly arranged on the rotary table 3, so that the sliding table 4 can be stably arranged on the rotary table by utilizing the arrangement of the polished rod 9.
Further, an opening slide rail 31 is detachably and fixedly arranged on the rotary table 3, the moving object is slidably arranged on the opening slide rail 31, the stop block 63 penetrates through the middle part of the opening slide rail, the stop block 63 is arranged below the rotary table 3, and the opening pair of the opening guide rail 31 is positioned on the pressure sensor 41, so that the moving object can slide along the opening guide rail 31 and can impact the pressure sensor 41 along with the rotation of the rotary table 3.
Secondly, set firmly a first locating part 01 and a second locating part 02 on the carousel 3 detachably, slip table 4 is subject to and moves between first locating part 01 and the second locating part 02 to utilize the setting of first locating part 01 and second locating part 02, be convenient for restrict the movable distance of slip table 4, wherein, one side of slip table 4 towards the face of 3 centre of a circle of carousel is located to first locating part 01 interval counterpoint, one side of the face of 3 centre of a circle of slip table 4 is kept away from to slip table 4 is located to second locating part 02 interval counterpoint, the base 91 of polished rod and the setting of second locating part 02 counterpoint interval.
Furthermore, the invention can also comprise a supporting seat 03, wherein a master control circuit module is arranged on the supporting seat 03, the turntable motor 1 is fixedly arranged on the supporting seat 03, an output shaft of the turntable motor 1 is connected with a perforated adapter 11, a conductive slip ring is arranged in the perforated adapter 11, a connecting wire 05 of the master control circuit module is wound in the conductive slip ring and extends out of a hole of the perforated adapter 11, and is connected to the turntable motor 1, the lead screw motor 2, the diffuse reflection laser sensor 7 and the resistance ruler 5, and the connecting wire 05 can rotate and can not be wound by the arrangement of the conductive slip ring and the perforated adapter 11; and in order to facilitate the arrangement of the connecting line 05, the bracket 8 can be in an inverted L shape.
In addition, a speed regulation potentiometer 041 capable of regulating the speed of the turntable motor 1, a screw rod motor control circuit module 042, a turntable motor control circuit module 043 and an AD conversion circuit module 044 can be arranged on the master control circuit module, the speed regulation potentiometer 041 is electrically connected with the turntable motor control circuit module 043 and the turntable motor 1, the screw rod motor control circuit module 042 is electrically connected with the screw rod motor 2, and the diffuse reflection laser sensor 7 and the resistance ruler 5 are electrically connected with the AD conversion circuit module 044, so that the turntable motor 1, the screw rod motor 2, the diffuse reflection laser sensor 7 and the resistance ruler 5 can be controlled conveniently.
The moving object may be a trolley 61, but is not limited thereto; the trolley 61 can be provided with a fixed rod 64, the fixed rod 64 is selectively provided with weights 62, so that the period of the uniform-speed circular motion of the moving object and the radius of the uniform-speed circular motion of the moving object can be kept unchanged by increasing or decreasing the weights 62, the masses of the moving objects are different, and the relationship between the pressure of a plurality of groups of moving objects on the sliding table 4 and the mass of the moving objects measured by the invention is observed.
The invention also discloses a radius calculation method for a moving object to do uniform circular motion, which applies the centripetal force experiment device, wherein the width of the stop block 63 (namely the distance between the front edge a and the rear edge b of the stop block 63) is equal to the displacement delta L of the moving object in delta t time, and the method comprises the following steps:
the method comprises the following steps: benefit toMeasuring delta t by using the diffuse reflection laser sensor 7, namely the time t when the front edge a of the stop block 63 is aligned with and blocks the diffuse reflection laser sensor 71The time t for the rear edge b of the stop block 63 to block the diffuse reflection laser sensor 7 in alignment2,t1、t2Measured by a diffuse reflection laser sensor 7, t ═ t2-t1；
Step two: calculating the time difference of the diffuse reflection laser sensor 7 at the opposite position on the central axis of the stop block 63 for two times by using the diffuse reflection laser sensor 7, namely the period T of the uniform circular motion of the moving object;
step three: calculating the rotating angle of the moving object in the time delta T according to the value alpha ═ delta T/T multiplied by 360;
step four: according to
And calculating the radius of the moving object in uniform circular motion.
While the invention has been described with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should not be limited to the embodiments disclosed, but includes various alternatives and modifications without departing from the present invention, which are encompassed by the claims.
Claims (10)
1. A centripetal force testing device, comprising: the device comprises a turntable motor, a screw motor, a turntable, a sliding table, a resistance ruler, a moving object and a diffuse reflection laser sensor, wherein the turntable motor drives the turntable to do uniform circular motion;
a screw rod of the screw rod motor drives the sliding table to move towards the center of the rotary table or move away from the center of the rotary table, and the screw rod motor is detachably and fixedly arranged on the rotary table;
the transmission shaft of the resistance ruler is telescopically connected and fixed on the sliding table, and the resistance ruler is detachably and fixedly arranged on the rotary table;
and a stop block is convexly extended below the moving object, and when the moving object rotates for a circle, the opposite point on the central axis of the stop block can be opposite to the diffuse reflection laser sensor once.
2. The centripetal force experiment device according to claim 1, wherein: the diffuse reflection laser sensor is detachably and fixedly arranged on the surface of the support facing the stop block.
3. A centripetal force testing device according to claim 2, wherein: the support is of an inverted L shape.
4. The centripetal force experiment device according to claim 1, wherein: a polish rod is arranged on the sliding table in a penetrating mode, and a base of the polish rod is detachably and fixedly arranged on the rotary table.
5. The centripetal force experiment device according to claim 1, wherein: an opening slide rail is detachably and fixedly arranged on the rotary table, the moving object is slidably arranged on the opening slide rail, the stop block penetrates through the middle of the opening slide rail, and the stop block is arranged below the rotary table.
6. The centripetal force experiment device according to claim 1, wherein: the turntable is detachably and fixedly provided with a first limiting piece and a second limiting piece, and the sliding table is limited by the movement between the first limiting piece and the second limiting piece.
7. The centripetal force experiment device according to claim 1, wherein: still include the supporting seat, be equipped with total control circuit module on the supporting seat, the carousel motor sets firmly on the supporting seat, a foraminiferous adapter is taken in the connection on the output shaft of carousel motor, be equipped with a conductive slip ring in the foraminiferous adapter, total control circuit module's connecting wire is around establishing to conductive slip ring in to stretch out the hole of foraminiferous adapter, and be connected to carousel motor, lead screw motor, diffuse reflection laser sensor and resistance ruler.
8. The centripetal force testing device according to claim 7, wherein: the general control circuit module is provided with a speed regulation potentiometer, a screw rod motor control circuit module, a turntable motor control circuit module and an AD conversion circuit module, wherein the speed regulation potentiometer can regulate the speed of the turntable motor, the speed regulation potentiometer is electrically connected with the turntable motor control circuit module and the turntable motor, the screw rod motor control circuit module is electrically connected with the screw rod motor, and the diffuse reflection laser sensor and the resistance ruler are electrically connected with the AD conversion circuit module.
9. The centripetal force testing device according to claim 8, wherein: the trolley is provided with a fixed rod, and weights are selectively arranged on the fixed rod.
10. A method for calculating the radius of a moving object making a uniform circular motion, wherein the centripetal force experiment device according to any one of claims 1 to 9 is applied, and the width of the stopper is equal to the displacement Δ L of the moving object in the time Δ t, comprising the following steps:
the method comprises the following steps: measuring delta t by using a diffuse reflection laser sensor, namely the time t when the front edge of the stop block is aligned to block the diffuse reflection laser sensor is t1The time for the rear edge of the stop block to face and block the diffuse reflection laser sensor is t2,t1、t2Measured by a diffuse reflection laser sensor, t ═ t2-t1；
Step two: calculating the time difference of the two diffuse reflection laser sensors in the opposite position on the central axis of the stop block by using the diffuse reflection laser sensors, namely the period T of the uniform circular motion of the moving object;
step three: calculating the rotating angle of the moving object in the time delta T according to the value alpha ═ delta T/T multiplied by 360;
step four: according to
And calculating the radius of the moving object in uniform circular motion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011118466.3A CN112133169A (en) | 2020-10-19 | 2020-10-19 | Centripetal force experiment device and radius calculation method for moving object to do uniform-speed circular motion |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011118466.3A CN112133169A (en) | 2020-10-19 | 2020-10-19 | Centripetal force experiment device and radius calculation method for moving object to do uniform-speed circular motion |
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| CN112133169A true CN112133169A (en) | 2020-12-25 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113376647A (en) * | 2021-06-08 | 2021-09-10 | 东北大学 | Blast hole measurement auxiliary equipment and use method thereof |
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2020
- 2020-10-19 CN CN202011118466.3A patent/CN112133169A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113376647A (en) * | 2021-06-08 | 2021-09-10 | 东北大学 | Blast hole measurement auxiliary equipment and use method thereof |
| CN113376647B (en) * | 2021-06-08 | 2024-04-26 | 东北大学 | Blast hole measurement auxiliary equipment and application method thereof |
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