CN204166148U - A kind of device measuring acceleration of gravity - Google Patents

Abstract

The utility model discloses a kind of device measuring acceleration of gravity, it comprises a container and a motion carrier, and wherein, described container is fixed on described motion carrier, and accommodates liquid in described container; Described motion carrier can do even acceleration or uniformly retarded motion, and the acceleration of this even acceleration or uniformly retarded motion can be obtained.Device of the present utility model can also comprise the device that the constant force of force application apparatus and carrying out for the acceleration of described motion carrier apply to(for) described motion carrier is measured.The device of measurement acceleration of gravity of the present utility model has that structure is simple, easy and simple to handle, measuring accuracy is high, measures the advantage that demonstration is vivid.

Description

A device for measuring the acceleration of gravity

technical field

The utility model relates to the technical field of gravitational acceleration measurement, in particular to a device for measuring gravitational acceleration.

Background technique

Test gravity acceleration in the prior art and generally use simple pendulum test, device comprises thin wire, metal ball with hole, iron clip, iron frame platform and stopwatch; , pass the thin wire through the hole on the metal ball to make a pendulum, fix the pendulum on the iron stand through the iron clip, place the iron stand on the edge of the table so that the iron clip protrudes from the table, and let the pendulum hang down freely ; Use a vernier caliper to measure the diameter of the ball and record it as d; use a meter ruler to measure the distance from the suspension point of the metal ball to the upper end of the ball and record it as 1; offset the metal ball by 5 to 8 degrees from the vertical line in the vertical plane Swing freely, and use a stopwatch to record the time T that the metal ball completes 30 to 50 full vibrations; find the average time t=T/c used by the metal ball for each full vibration; where c is the metal ball within T time. The number of full vibrations made by the ball; the acceleration of gravity is obtained according to the formula g=4π ² L/t ² , where L=d/2+1.

When using the device in the prior art to test the acceleration of gravity, one person needs to watch the watch and one person records the number of times of the full vibration of the pendulum. It takes a lot of repeated operations to make a successful measurement, so it takes a relatively long time to measure the acceleration of gravity using the acceleration of gravity measuring device in the prior art.

Utility model content

(1) Technical problems to be solved

What the utility model aims to solve are the shortcomings of the existing device for measuring the acceleration of gravity, such as complicated operation, poor accuracy and long time consumption.

(2) Technical solutions

The device for measuring the acceleration of gravity of the utility model comprises a container and a motion carrier, wherein, the container is fixed on the motion carrier, and liquid is contained in the container; the motion carrier can perform uniform acceleration or uniform acceleration. Deceleration motion, and the acceleration of the uniform acceleration or uniform deceleration motion can be obtained.

According to a specific embodiment of the present utility model, a height scale is provided on the wall of the container.

According to a specific embodiment of the present invention, the moving device can perform uniform acceleration or uniform deceleration with a preset acceleration.

According to a specific embodiment of the present invention, a force applying device is also included, and the force applying device can apply a constant force to the combination of the container and the moving carrier.

According to a specific embodiment of the present invention, an acceleration measuring device is also included, which is used to measure the acceleration of the moving carrier.

According to a specific implementation manner of the present utility model, the acceleration measuring device is a gyroscope.

According to a specific embodiment of the present invention, the acceleration measuring device is a detector arranged at a certain distance on the moving path of the moving carrier.

According to a specific embodiment of the present invention, the viscosity of the liquid is lower than 20 centipoise at room temperature.

According to a specific embodiment of the present utility model, the liquid is water.

(3) Beneficial effects

The device for measuring the acceleration of gravity of the utility model has the advantages of simple structure, convenient operation, high measurement precision, and vivid measurement demonstration.

Description of drawings

Fig. 1 is the structural representation of the device for measuring the acceleration of gravity of the utility model;

Fig. 2 is a schematic diagram of the device for measuring the acceleration of gravity of the present invention, which shows the force situation of a point on the liquid surface.

Detailed ways

In order to solve the above technical problems, the utility model proposes a new device for measuring the acceleration of gravity, which includes a container and a moving carrier, wherein the container is fixed on the moving carrier, and the container contains liquid , the wall of the container is provided with a height scale; the moving carrier can be uniformly accelerated or uniformly decelerated.

Fig. 1 is a structural schematic diagram of a device for measuring the acceleration of gravity of the present invention. As shown in FIG. 1 , the measuring device of the present invention includes a container 1 and a moving carrier 2 . The container 1 is fixed on the moving carrier 2 and contains a liquid 3 therein.

The shape of the container 1 is not limited in the present invention, it can be cup-shaped, cylindrical, prism-shaped, etc., and its material is preferably transparent or translucent, so as to observe the liquid level from the outside. The height scale is preferably marked on the container wall, so as to record the position of the liquid level. The height scale is preferably located at least on the front and back sides along the moving direction of the moving carrier 2 , so as to observe the liquid level on the front and back sides.

The motion carrier 2 can perform uniformly accelerated motion or uniformly decelerated motion under the action of external force. Preferably, the force applying device for applying the external force can apply a constant force to the motion carrier 2 . The force may be a mechanical force, an electric field force, a magnetic field force, or the like. For example, the force applying device may be a device that applies a constant magnetic field on the moving track of the moving carrier 2, and at least a small part of the moving carrier 2 is a magnet.

The moving carrier 2 is preferably placed on a contact plane with a constant friction coefficient, so that the frictional force it receives during the movement remains constant. The desired moving carrier 2 can generate sliding friction or rolling friction with the plane on which it is placed when moving. For example, as shown in Figure 1, small wheels are installed at the bottom to generate rolling friction with the contact surface.

Thus, when the force applying device (not shown in Fig. 1) exerts a constant force on the moving carrier, the container 1 along with the moving carrier 2 moves toward the direction of the applied force with acceleration or deceleration (depending on the motion The direction of the initial velocity of the carrier 2 is the same as or opposite to the direction of the applied force), thus, the liquid level of the liquid in the container 1 will generate an inclination angle α. Next, let's analyze the principle of using the inclination angle to measure the acceleration of gravity.

Fig. 2 is the schematic diagram of the device for measuring the acceleration of gravity of the present utility model, and what it shows is the stressed situation of a point on the liquid surface, gets a tiny volume element (liquid microelement) on the liquid surface of described liquid 3 , assuming its mass is m, its gravity is mg. At the same time, it is also supported by the support force N given by the liquid below. The direction of the support force N is perpendicular to the direction of the liquid surface. The resultant force of the support force N and the gravity mg That is to make the liquid element produce the resultant force of acceleration a, thus mg·tgα=ma can be obtained. So g=a/tg α. At the same time, as shown in Figure 1, tg α is the quotient of the height difference Δh between the front and back of the liquid and the distance D between the front and back of the liquid, that is, tg α=Δh/D. Substituting into the previous formula, g=a·Δh/D can be obtained.

Since the height difference Δh and acceleration a of the liquid front and back can be easily obtained, the distance D between the front and back of the liquid is usually a fixed value, so as long as the moving carrier 2 performs uniform acceleration or deceleration once or more times, the value of the acceleration of gravity can be obtained .

Of course, the size of the angle α can also be directly measured in other ways, such as obtaining an image of the liquid level through real-time image recording, and then obtaining the size of the angle through measurement.

The acceleration a of the uniformly accelerated or uniformly decelerated motion should be preset or can be accurately measured. If it is pre-designed, the constant force exerted by the force applying device on the container and the moving carrier can be precisely adjusted, for example, by adjusting the strength of the constant magnetic field, and then the magnitude of the magnetic field strength and the magnitude of the acceleration can be calibrated , the predetermined acceleration can be adjusted according to the set magnetic field strength.

If the acceleration a is measured during the experiment, two detectors can be arranged at a certain distance on the motion track of the moving carrier 2, which are respectively used to detect the time when the moving carrier 2 passes through the two detectors, Thus, after calculating the time difference t between the two time points, the minimum acceleration can be obtained according to the formula a=2s/t ² , where s is the distance between the two detectors.

Of course, if the magnitude of the applied constant force cannot be accurately designed, or it is inconvenient to measure the total mass of the container and the moving carrier, an acceleration measuring device may be used to measure the acceleration of the moving carrier 2 in uniformly accelerating or uniformly decelerating motion . The acceleration measuring device is, for example, a gyroscope mounted on a moving carrier.

In addition, the viscosity of the liquid contained in the container should be as small as possible, so as not to take too long for the liquid to reach equilibrium after changing from a static state to a uniform acceleration/deceleration state. Generally, a liquid with a viscosity below 20 centipoise at room temperature can be selected, and water is a preferred choice.

Compared with the prior art of directly measuring the acceleration, the utility model converts the acceleration measurement in the vertical direction into the acceleration measurement in the horizontal direction through the tilt effect that occurs when the liquid accelerates, which is beneficial to improve the difficulty of the structure of the measuring device. Thereby improving the accuracy of measurement. Simultaneously, the measuring method of the utility model is simple and effective, and can improve the measuring effect. Simultaneously, the measurement process of the utility model is vivid and vivid, and can be applied to experimental equipment in teaching and scientific research, so as to improve the vividness and quality of teaching.

The above-mentioned specific embodiments have further described the purpose, technical solutions and beneficial effects of the present utility model in detail. It should be understood that the above-mentioned descriptions are only specific embodiments of the present utility model, and are not intended to limit the present utility model. For new models, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims (9)

1. A device for measuring the acceleration of gravity, comprising a container and a motion carrier, wherein, The container is fixed on the moving carrier, and liquid is contained in the container; The motion carrier can perform uniform acceleration or uniform deceleration, and the acceleration of the uniform acceleration or uniform deceleration can be obtained. 2. The device for measuring gravitational acceleration according to claim 1, wherein a height scale is arranged on the wall of the container. 3. The device for measuring gravitational acceleration according to claim 1, characterized in that, the moving device can perform uniform acceleration or uniform deceleration with a preset acceleration. 4. The device for measuring the acceleration of gravity according to claim 3, further comprising a force applying device capable of exerting a constant force on the combination of the container and the moving carrier. 5. The device for measuring the acceleration of gravity according to any one of claims 1 to 4, further comprising an acceleration measuring device for measuring the acceleration of the moving carrier. 6. The device for measuring the acceleration of gravity according to claim 5, characterized in that, the acceleration measuring device is a gyroscope. 7. The device for measuring the acceleration of gravity according to claim 5, wherein the acceleration measuring device is a detector arranged at a certain distance on the moving path of the moving carrier. 8. The device for measuring the acceleration of gravity according to any one of claims 1 to 4, wherein the viscosity of the liquid is lower than 20 centipoise at normal temperature. 9. The device for measuring the acceleration of gravity according to any one of claims 1 to 4, wherein the liquid is water.