CN202677673U

CN202677673U - Experimental device for testing mechanical energy and momentum conservation

Info

Publication number: CN202677673U
Application number: CN 201220345138
Authority: CN
Inventors: 刘永智; 吴贤忠; 苏成仁; 李海翼
Original assignee: 刘永智
Priority date: 2012-07-17
Filing date: 2012-07-17
Publication date: 2013-01-16
Anticipated expiration: 2022-07-17

Abstract

The utility model provides an experimental device for testing mechanical energy and momentum conservation to solve the problem that the testing experiment of the law of mechanical energy conservation and the law of momentum conservation may be affected by factors such as friction and gravitational acceleration measurement and the like. The experimental device comprises an iron support stand, wherein a white paper and a copy paper are laid on one side of the iron support stand sequentially from down to top; the top end of the iron support stand is provided with a fixed shaft; the fixed shaft is connected with a swinging rod capable of swinging laterally; the tail end of the swinging rod is connected with a first metal ball; the iron support stand is further provided with a dial and a blocking rod used for blocking the swinging rod; a supporting rod is arranged on one side, on which the white paper is laid, of the iron support stand; a second metal ball is placed on the top part of the supporting rod; and when the swinging rod is perpendicular to the bottom surface of the iron support stand, the first metal ball and the second metal ball are in the same horizontal plane. The problem that a previous experiment for testing the law of mechanical energy conservation is constrained by the measurement of local gravitational acceleration is avoided; and meanwhile the influence of friction is reduced and the testing results are more accurate with the experimental device adopted.

Description

The experimental provision of checking mechanical energy and momentum conservation

Technical field

The utility model relates to the dynamics experimental device in the physics teaching, and is particularly a kind of for checking conservation of mechanical energy and momentum conservation experiment.

Background technology

At present, the most popular method that adopts when doing the confirmatory experiment of the law of conservation of mechanical energy is the flat proof method of throwing of falling bodies proof method, skewed slot, with these method validation conservation of mechanical energy the time, since exist the frictional resistance of windage resistance, skewed slot and local gravitational acceleration determination influences the checking conclusion, the reduction of gravitional force was also less than the recruitment of kinetic energy when bead fell, and this obviously runs counter to law of conservation of energy; Secondly bead speed is difficult for accurate Calculation, and rate error is larger, thereby causes experiment conclusion and theoretical value not to be inconsistent, and affects the student for understanding and the learning interest of physical knowledge.Often adopt the air track slide block to collide to verify doing the law of conservation of momentum, and that this device requires is very high, not easy to operate to the adjustment of level, secondly, this device popularity rate is not high.

The utility model content

The purpose of this utility model provides a kind of experimental provision of verifying mechanical energy and momentum conservation, to solve the impact of the factor such as friction force, local gravitational acceleration mensuration when doing the confirmatory experiment of the law of conservation of mechanical energy and the law of conservation of momentum in the prior art.

For achieving the above object, the utility model is by the following technical solutions:

A kind of experimental provision of verifying mechanical energy, comprise iron stand, one side of described iron stand is equipped with blank sheet of paper and transfer paper from the bottom up successively, the top of described iron stand is provided with stationary shaft, but described stationary shaft is connected with the swing arm of teeter, the tail end of described swing arm is connected with the first prill, also is provided with index dial on the described iron stand and is used for stopping the countercheck rod of swing arm.

The junction of the tail end of described swing arm and the first prill is " U " font.

Swing arm is that elasticity and hardness are large, the steel wire about diameter 1mm is made, described the first prill is provided with duck eye, and described the first prill is enclosed within on the described swing arm by duck eye, and little hole dia is greater than the diameter of swing arm, the degree of depth of duck eye is to the centre of sphere, inner wall smooth.

A kind of experimental provision of verifying momentum conservation, comprise iron stand, one side of described iron stand is equipped with blank sheet of paper and transfer paper from the bottom up successively, the top of described iron stand is provided with stationary shaft, but described stationary shaft is connected with the swing arm of teeter, the tail end of described swing arm is connected with the first prill, also be provided with index dial on the described iron stand and be used for stopping the countercheck rod of swing arm, the side that described iron stand is equipped with blank sheet of paper is provided with pole, described pole top is placed with the second prill, when swing arm during perpendicular to the iron stand bottom surface, the first prill and the second prill be in same level.

The diameter of described the first prill and the second prill, identical in quality.

Utilize simple harmonic motion and level throw motion to combine, directly measure the variable quantity h of the first last position that causes potential variation, the vertical height H of level throw motion and the amount of horizontal shift x, utilize

Figure 2012203451381100002DEST_PATH_IMAGE001

This relation can directly be verified the law of conservation of mechanical energy and the law of conservation of momentum.Thereby avoided verifying that the law of conservation of mechanical energy is limited by local gravitational acceleration and measures, this experimental provision has also reduced the impact of friction force simultaneously, so that the result is more accurate in the past; Secondly this device simpler, easily make, cost is low, for the checking law of conservation of momentum and the law of conservation of mechanical energy provide easily experimental provision.

Description of drawings

Fig. 1 is structural representation of the present utility model;

Fig. 2 is the side view of Fig. 1.

Embodiment

Below in conjunction with accompanying drawing the utility model is described further.

The checking law of conservation of mechanical energy:

As depicted in figs. 1 and 2, a kind of experimental provision of verifying mechanical energy, comprise iron stand 3, one side of iron stand 3 is equipped with blank sheet of paper 1 and transfer paper 2 from the bottom up successively, the top of iron stand 3 is provided with stationary shaft 6, but stationary shaft 6 is connected with the swing arm 7 of teeter, and the tail end of swing arm 7 is connected with the first prill 9, also is provided with index dial 5 on the iron stand 3 and is used for stopping the countercheck rod 4 of swing arm 7.

The junction of the tail end of swing arm 7 and the first prill 9 is " U " font.

Swing arm 7 is for elasticity and hardness is large, the steel wire about diameter 1mm is made, and the first prill 9 is provided with duck eye, and the first prill 9 is enclosed within on the swing arm 7 by duck eye, and little hole dia is greater than the diameter of swing arm 7, and the degree of depth of duck eye is to the centre of sphere, inner wall smooth.

The paper size of blank sheet of paper 1 and transfer paper 2 is A3.

The implementation step is as follows:

1. at the blank sheet of paper 1 of an A3 size of smooth experiment table tiling, the above's transfer paper 2 that tiles;

2. iron stand 3 is placed on the blank sheet of paper 1 of tiling and the transfer paper 2 and the adjustment level, successively constant resistance bar 4, index dial 5 and stationary shaft 6 on iron stand 3; Countercheck rod 4 is avoided bending behind the multiple impacts near the lower end with the swing arm of " U " font;

3. adjust a side of the center of center, index dial 5 of stationary shaft 6 and countercheck rod 4 at same vertical position with pedal line;

4. will be suspended on the swing arm 7 of U font on the stationary shaft 6, the first prill 9 will be enclosed within on the swing arm 7 of U font;

5. cover there is the swing arm 7 of the first prill 9 to draw high together static release behind a certain position, measures the first last location variation h that causes the first prill potential variation, the vertical height H of level throw motion and the data of horizontal shift x; Above-mentioned measurement data substitution formula

The checking conservation of mechanical energy.

The checking law of conservation of momentum:

As depicted in figs. 1 and 2, a kind of experimental provision of verifying momentum conservation, comprise iron stand 3, one side of iron stand 3 is equipped with blank sheet of paper 1 and transfer paper 2 from the bottom up successively, the top of iron stand 3 is provided with stationary shaft 6, but stationary shaft 6 is connected with the swing arm 7 of teeter, the tail end of swing arm 7 is connected with the first prill 9, also be provided with index dial 5 on the iron stand 3 and be used for stopping the countercheck rod 4 of swing arm 7, the side that iron stand 3 is equipped with blank sheet of paper 1 is provided with pole 8, pole 8 tops are placed with the second prill 10, when swing arm 7 during perpendicular to iron stand 3 bottom surface, the first prill 9 and the second prill 10 be in same level.

The diameter of the first prill 9 and the second prill 10, identical in quality.

The paper size of blank sheet of paper 1 and transfer paper 2 is A3.

Concrete steps are as follows:

5. place cylinder pole 8 below countercheck rod 4, the second prill is placed on its top makes the contact point of itself and the first prill and stationary shaft 6 centers at same vertical position.

6. cover there is the swing arm 7 of the first prill 9 to draw high together static release behind a certain position, measures parameters, according to the formula checking law of conservation of momentum.

Claims

1. experimental provision of verifying mechanical energy, it is characterized in that: comprise iron stand (3), one side of described iron stand (3) is equipped with blank sheet of paper (1) and transfer paper (2) from the bottom up successively, the top of described iron stand (3) is provided with stationary shaft (6), described stationary shaft (6) but be connected with the swing arm (7) of teeter, the tail end of described swing arm (7) is connected with the first prill (9), also is provided with index dial (5) on the described iron stand (3) and is used for stopping the countercheck rod (4) of swing arm (7).

2. the experimental provision of checking mechanical energy as claimed in claim 1 is characterized in that: the junction of the tail end of described swing arm (7) and the first prill (9) is " U " font.

3. the experimental provision of checking mechanical energy as claimed in claim 1 or 2, it is characterized in that: swing arm (7) is for elasticity and hardness are large, steel wire about diameter 1mm is made, described the first prill (9) is provided with duck eye, described the first prill (9) is enclosed within on the described swing arm (7) by duck eye, little hole dia is greater than the diameter of swing arm (7), the degree of depth of duck eye is to the centre of sphere, inner wall smooth.

4. the experimental provision of checking mechanical energy as claimed in claim 3, it is characterized in that: the paper size of described blank sheet of paper (1) and transfer paper (2) is A3.

5. experimental provision of verifying momentum conservation, it is characterized in that: comprise iron stand (3), one side of described iron stand (3) is equipped with blank sheet of paper (1) and transfer paper (2) from the bottom up successively, the top of described iron stand (3) is provided with stationary shaft (6), described stationary shaft (6) but be connected with the swing arm (7) of teeter, the tail end of described swing arm (7) is connected with the first prill (9), also be provided with index dial (5) on the described iron stand (3) and be used for stopping the countercheck rod (4) of swing arm (7), the side that described iron stand (3) is equipped with blank sheet of paper (1) is provided with pole (8), described pole (8) top is placed with the second prill (10), when swing arm (7) during perpendicular to iron stand (3) bottom surface, the first prill (9) and the second prill (10) be in same level.

6. the experimental provision of checking momentum conservation as claimed in claim 5 is characterized in that: the diameter of described the first prill (9) and the second prill (10), identical in quality.

7. the experimental provision of checking momentum conservation as claimed in claim 6, it is characterized in that: the paper size of described blank sheet of paper (1) and transfer paper (2) is A3.