Isothermal change

Keeps

1. Requirements in physical knowledge:

(l) know what is aimed to change;

(2) know the lobular poor romance is an experimental law; master the content and formula of the law of vane Know the application of the law.

(3) Understand the physical meaning of the P-V image of the gas isothermal;

(4) know the qualitative interpretation of the law of the via theory of vanity;

(5) The problem associated with the liprological ear apronization.

2. Through the study of demo experiments, cultivate students' observations, analytical capabilities, and ability to physically have physical laws from experiments.

3. Education for penetrating physics research: When you need to study the relationship between two or more physical quantities, first keep one or a few physical quantities unchanged, start research from the simplest situation, draw some law, then further study The relationship between the various physical quantities involved.

focus, difficulty analysis

1. The focus is the relationship between the student knows and masters the relationship between the pressure and volume of a certain mass of the gas, understands the physical significance of the P-V image, and knows the application of the law of the polish.

2. Students often have a failure of "status" and "process", causing causing shortprints, confusing problems in different processes, this is a difficult point. At this stage, there are quite a multi-student that does not correctly determine the pressure of the closed gas.

Technique

1. Qualitatively demonstrates a certain mass of gas to maintain the relationship between pressure and volume of the temperature and volume at the temperature of the temperature and volume.

rubber membrane (or balloon skin), a transparent plastic scale opening between 5 cm left and right (about 25 cm), A homemade piston matching a brief diameter, a piece of 20 cm × 6cm, assembled as a picture.

2. It is more accurately demonstrated that a certain quality gas is in the temperature remained unchanged. The relationship between the pressure and volume of the volume is

experimental instrument as shown in the following figure "isothermal change".

Using the presentation

Main teaching process:

(1) introduced new class

research process of the second law of Newton m must, α-αf; then f must; finally, select the appropriate unit.

Now we use this research method of control conditions to study the relationship between gas state parameters.

(2) Teaching process design

The gas remains temperature constant, pressure and volume.

(3) Experimental Conclusion

experimental data indicate:

a quality gas, under the conditions of temperature constant, the volume is reduced to the original alert One, its pressure is increased to several times;

a certain quality gas, under the condition of the temperature, the volume increases to several times, its pressure reduces For the original one in the original.

experiment summary

1. A certain gas gas, in the case of the temperature constant, its pressure is inversely proportional to the volume.

2. The vinylothelial law can be represented by P-V.

3. The lippar is the law is the law of the experiment, no matter what gas, as long as the pressure is not too large (and atmospheric comparison), the temperature is less low (and room temperature comparison), it is approximately in line with this law.

Description:

1. Other methods can also be used in demonstration experiments, as long as the gas quality must be satisfied, the temperature is unchanged.

2. Students are the first contact state analysis, and the students must require students to write initial states and last stateful state parameters to develop good habits.

3. The first content of the teaching process design is to help students get ways to create isothermal conditions, as appropriate.