I. teaching material analysis
"Temperature" is the first section of the third chapter "Changes of Physical State" in junior high school physics textbooks published by People's Education Press. The teaching of this chapter starts with "temperature" and "use of thermometer", not only because they are the preparatory knowledge of this chapter, but also because the change of material state revolves around "whether the temperature changes". It can be said that "temperature" is the core of "the change of material state", and learning to use "thermometer" is the basic skill of learning this chapter.
Second, the analysis of learning situation
Grade eight students are active in thinking, curious and eager for knowledge, but weak in practical ability. In addition, they have just come into contact with physics and lack understanding of the basic links and necessary logical knowledge of scientific inquiry. Therefore, we should introduce the common phenomena of students, so that students can gradually understand and apply scientific knowledge. It is not difficult for students to understand the temperature in their daily life. Although the students of "thermometer" may have come into contact with it in daily life, there are still some doubts about the making principle and operating specifications of thermometer. Therefore, we should pay attention to training students to describe concepts in scientific terms, standardize the use of thermometers to measure temperature, and highlight the education of scientific methods.
Third, the teaching objectives
Knowledge and skills
1, understand the concept of temperature;
2. Understand the common temperature values in the living environment; 3, will use a thermometer to measure the temperature. Process and method
1, and understand the structure of the thermometer through observation and experiment;
2. Let students master the use of thermometers through learning activities. Emotions, attitudes and values
Through teaching activities, students' interest in learning and thirst for knowledge of science are stimulated, and students are willing to explore natural phenomena and physical principles in daily life.
Fourth, the teaching focus and difficulties
Key points: the concept of temperature; Correct use of thermometer to measure temperature, and can read the readings of various thermometers. Difficulties: the structure and principle of thermometer; Comparison between clinical thermometer and laboratory thermometer
Five, teaching preparation
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Jar, colored water, rubber stopper, thin glass tube, experimental thermometer, thermometer, beaker (3 for each table, medium size), multimedia courseware, boiled water and cold water.
Sixth, the teaching process.
three
Seven, blackboard design
4- 1 thermometer
1, the concept of temperature: temperature is the degree to which an object is hot or cold. 2. Provisions for the centigrade scale: (1) symbol:℃.
(2) The temperature of the ice-water mixture at one atmospheric pressure is 0℃; The temperature of boiling water is 100℃. 3. Thermometer
(1) structure: glass bulb, glass tube, capillary tube, etc. (2) Working principle: liquid expands when heated and contracts when cooled. 4. Thermometer
(1) measuring range: 35-42℃ (2) dividing value: 0. 1℃
(3) Structure: Bend the thin glass tube and shake it before use.
four
Chapter 2: Teaching plan of the quality class "Temperature" in the fourth chapter of eighth grade physics published by People's Education Press.
The first section temperature teaching design
Teaching objectives:
1. Knowledge and skill objectives:
(1) Know that the temperature indicates the degree of heat and cold of an object, and know the stipulation that the temperature is in degrees Celsius.
(2) Understand the working principle of liquid thermometer and measure the temperature with thermometer.
(3) Cultivate students' practical ability and self-study ability.
2. Process and method objectives:
(1) Cultivate students' ability to observe, analyze and ask questions.
(2) Initially cultivate students' creative thinking and creativity.
3. Emotional attitudes and values goals:
(1) Cultivate students' rigorous scientific attitude and healthy mentality of mutual cooperation and friendly coexistence.
(2) Cultivate students' awareness of caring for the environment.
Description: The setting of teaching objectives fully embodies the concept of physics curriculum standards. In this teaching, students should not only understand the principle and structure of thermometer, but also master basic knowledge and skills such as correct use of thermometer. More importantly, this class takes the above knowledge as the carrier to cultivate students' scientific attitude of being willing to explore and be brave in innovation and their healthy psychology of mutual cooperation and friendly coexistence, thus cultivating students' interest in learning physics. )
Teaching focus:
1. With the self-made demonstration thermometer as equipment, the principle and structure of liquid thermometer are obtained through students' observation, analysis and creation.
2. Through students' hands-on experiments, reading textbooks and discussing with each other, how to use the thermometer correctly is summarized.
Teaching difficulties:
How to gradually cultivate the autonomous learning consciousness of underachievers in the teaching process?
(Note: The establishment of teaching emphases and difficulties focuses on cultivating students' practical ability, self-study ability, observation ability, analytical ability and creative ability, as well as cooperation consciousness and the ability to actively participate in learning. Teaching methods: observation experiment, self-study discussion and inquiry learning.
Teaching process:
First of all, introduce.
1. Show slides and students observe pictures.
Students talk about their feelings after observation and introduce the topic "temperature"
Second, new funding.
Section 1 temperature
2. Student experiment 1
Students touch the hot water cup and the cold water cup with their hands and tell their feelings. Guide students to summarize.
Concept of temperature: In physics, the degree of hot and cold of an object is called temperature. A cold object has a low temperature and a hot object has a high temperature.
Let some students touch two glasses of water.
Teacher: Is it accurate to judge the temperature by feeling? What should I do to know the temperature of an object accurately?
(1): Principle and structure of thermometer
Teacher: What thermometer do you know? What is its structure?
(Description: Cultivate students' ability to observe, think and ask questions. )
Students discuss and ask questions in groups.
(Description: The teacher writes down the problems to be solved in this class put forward by the students on the blackboard; Give praise to students who take the initiative to ask questions. Some students may ask questions that are inconsistent with this section. Teachers should not ignore them and give reasonable explanations. Don't discourage students from thinking and speaking.
1. The teacher demonstrated the homemade thermometer.
Teacher: Put this device into a beaker filled with hot water, and the students guess what will happen.
Students discuss and answer. The teacher put the device in a beaker filled with hot water, and the students observed it.
Teacher: Now take this device out of the hot water and put it in a beaker filled with cold water. What will happen? Students guess and answer.
The teacher took the equipment out of the hot water and put it in a beaker filled with cold water. Students observe phenomena.
Teacher: What is this phenomenon called?
Student: Thermal expansion and cold contraction.
Teacher: Can a temperature measuring device be made according to the principle that liquid expands when heated and contracts when cooled? What's the name of this equipment?
Student: Thermometer.
Teacher: Now who can tell the measuring principle of liquid thermometer?
The teacher held up a homemade thermometer.
Teacher: Can this device be used to measure the temperature of liquid? What defects do you think it has? (Note: The design of this topic is mainly based on students' observation, and students' enthusiasm for learning is mobilized through their emotional factors. )
The teacher took out the demonstration thermometer.
Teacher: This thermometer has been improved and is perfect. Now let's look at this thermometer. Are you satisfied?
Teacher: Who can describe the structure of this thermometer?
(2), Celsius temperature
1. Provisions on the temperature of Celsius
Students read the textbook P69 and discuss how to specify 0 degrees Celsius, 100 degrees Celsius and 1 degrees Celsius.
2. Read and write the temperature in Celsius: Show the draft of the weather forecast and let the students play the announcer to broadcast the weather forecast. Who wants to?
Weather forecast for Ningxia 20 12 65438+26 10.
Hello, audience friends! Ningxia will turn sunny and cloudy from night to tomorrow, with northerly winds of 3-4 and temperature of-15℃ to 2℃. It will be cloudy from night to day the day after tomorrow. The temperature is low recently, please pay attention to cold and warmth.
Students should read, encourage in time, correct misunderstandings and cultivate self-confidence.
3. Understand the structure of thermometer, and introduce the measuring range and dividing value of thermometer.
(3), the use of thermometer
Teacher: What should I do before using a thermometer?
Students read the textbook P49 "Use of Thermometer" and give feedback.
Teacher: What are the common mistakes in using thermometers? How to use the thermometer correctly?
Students read the main points of P49 thermometer and measure the temperature of water. Show in groups.
(Description: Through hands-on practice, self-study, discussion and demonstration, students summed up how to use thermometers correctly, which impressed them deeply and improved their self-study ability and problem analysis ability. )
The teacher simply summed up how to use the thermometer correctly;
(4), thermometer
1, the teacher shows the thermometer, and the students observe and know the structure of the thermometer, especially the function of necking. Teacher Range: Where have the students seen thermometers? What did the doctor do before using them?
Student: I have seen it in the hospital. Doctors should shake it a few times before using it.
Teacher: It's normal to be sick. Students should strengthen exercise and go to the hospital as little as possible.
(Note: Remind students to strengthen exercise and cultivate students' awareness of caring for their bodies) Students read P69 Thermometer.
Knowledge summary: students should be responsible for themselves.
(v) Summary
(6) Blackboard design
Section 1 temperature
1, the degree of heat and cold of an object is called temperature.
2. Thermometer
The specified temperature of (65438 0) degrees Celsius.
(2) the structure of the thermometer
(3) the use of thermometer
(4) Clinical thermometer and its use
The third chapter: the temperature teaching plan of the third chapter of the eighth grade physics in the new edition of People's Education Edition.
Section 1 temperature
Teaching objectives
1, knowledge and skills
● Understand the concept of temperature;
● Understand the common temperature values in the living environment;
● Will measure the temperature with a thermometer.
2. Process and method
● Understand the structure of thermometer through observation and experiment;
● Make students master the use of thermometers through learning activities;
3. Emotions, attitudes and values
● Stimulate students' interest in learning and curiosity for science through teaching activities, so that students are willing to explore natural phenomena and the sun.
Physical principles in daily life.
teaching process
First, create scenarios and introduce topics.
Teacher: In our daily life, we often hear such a dialogue: "It's so hot today!" "Yes, autumn is coming. Why is the temperature so high? " "But I get cold when I get up in the morning."
Teacher: From this conversation, we can know what they are discussing.
Health: cold, hot.
Teacher: In physics, the degree of heat and cold of an object is called temperature.
2. Put ice water, tap water and hot enough water in three beakers to guide students to experience "cold" and "hot". Teacher: Why does the same cup of tap water have two different cold and hot feelings almost at the same time?
Health: It seems that people's feelings are unreliable.
Teacher: In daily life, people often judge things according to their own experiences and feelings. However, these experiences and feelings are not all reliable, and sometimes mistakes occur. Therefore, in order to accurately judge the temperature, we must use the thermometer as a tool to measure the temperature.
Second, learn new knowledge step by step.
Teacher: Have you ever observed a similar phenomenon? When boiling water at home, if the water in the kettle is too full and the water just begins to boil, it will overflow.
Health: Yes.
Teacher: Good! Then we give it a physical name-the combination of thermal expansion and cold contraction, and the textbook P47 introduces the principle of thermometer.
Teacher: Thermometers are made according to the law that liquids expand when heated and contract when cooled. According to the different temperature measuring environment, the temperature measuring substance in the thermometer is generally different, which can be alcohol, mercury or kerosene. Ask students to observe various commonly used thermometers in Figure 3. 1-2.
Teacher: Different thermometers have their own wonderful uses. Today, we are studying the common glass liquid thermometers. Their structures are basically the same, including a liquid bubble, a thin inner tube and a glass column engraved with an indicator. According to the different liquids in the liquid bubble, alcohol thermometer, kerosene thermometer and mercury thermometer are usually used.
Teacher: Since temperature is a physical quantity used to measure the degree of heat and cold of an object, it should have its own unit. Let's find out the answer by observing the thermometer.
A. The letter "℃" means the temperature of Celsius (proposed by Poerxiusi, Sweden).
B 0℃ stipulates that the temperature of ice-water mixture is 0℃ at one atmospheric pressure (you will know more about "one atmospheric pressure" in later study).
C. Provisions of 100℃: At one atmospheric pressure, the temperature when water boils is recorded as100℃.
D. 1℃: divided between 0℃ and 100℃ 100 copies, each representing 1℃. The normal body temperature of the human body is 37℃, which is pronounced as 37℃. In the tent of Everest camp, the temperature is-15℃, pronounced as-15℃ or-15℃.
In CCTV reports, all the hosts read the temperature as: 100 degrees, 1600 degrees. Do you think it's appropriate? Test you with a question: "25℃". Do you understand? How to write "28 degrees Celsius"? How to write "MINUS 8 degrees Celsius"?
3. Try to explore and learn to use it.
Teacher: Look at the two thermometers on the experimental table. Can you tell the difference between them?
Health A: One takes a normal temperature, and the other takes a temperature.
Health B: The range of numbers marked on it is different.
Health C: Each cell represents a different temperature.
Health D: The bottom of the thermometer is bent.
Health E: The glass column of the thermometer is not round.
Health F: The glass column of the thermometer can play a magnifying role.
Teacher: Good! The students all made a careful observation. From today, learning measurement must comply with two requirements ── observation range and dividing value.
Range-The temperature range of the highest and lowest temperatures that can be measured. The measuring range of the thermometer used in the laboratory is-20℃ ~110℃. The measuring range of the thermometer is 35℃ ~ 42℃.
B. Dividing value-the smallest representative value. The calibration value of the thermometer used in the laboratory is 65438 0℃. The scale value of the thermometer is 0.65438 0℃.
(Students answer after observing)
Teacher: There are two thermometers in the air. Now the thermometer should read the temperature of the air. Please read them out. Student A: (holding the thermometer used in the laboratory) The reading is: (attention unit).
Health B: (holding a thermometer in his hand) I don't understand.
Teacher: Why don't you understand?
Health: The current temperature has not reached the lowest temperature that can be measured by thermometer.
Teacher: Good answer!
Third, summarize and consolidate knowledge.
Teacher: How time flies! In a blink of an eye, a class will be over. What have you gained from this course? Or how do you feel? Say it and share it with everyone, okay?
Student: (here students may have various statements to guide them to sum up what they have learned)
Conclusion: Students, after learning about temperature and thermometer, we will continue to explore and learn the usage of thermometer in the next class. Please get ready when you go back.
Additional exercises:
1. Xiaoming draws the following conclusions through research. Please help him finish them.
(1) The temperature of the ice-water mixture is _ _ _ _ _ _ _. The temperature of boiling water is _ _ _ _ _ _.
(2) The commonly used liquid thermometer is made according to the law of _ _ _ _ _ _. The liquid in the thermometer is usually _ _ _ _ _ _ _ (list two kinds).
(3) The letter "c" on the thermometer indicates that the thermometer adopts the temperature of _ _ _ _ _ _ _ _. The normal body temperature of a person is about _ _ _ _ _ _ _ _ _ _, which is pronounced as _ _ _ _ _ _ _.
(4) The thermometer commonly used in the laboratory has a _ _ _ _ _ _ _ at the lower end, with a _ _ _ _ _ _ _ with a very thin inner diameter attached to it. When the temperature changes slightly, the liquid level position in the thin tube will change.
2. Which one should I choose?
(1) temperature reflects the () of the object.
A. size B. movement speed C. degree of heat and cold D. vibration speed
(2) The correct pronunciation of-20℃ is ()
A. MINUS 20 degrees B. MINUS 20 degrees C. MINUS 20 degrees D.