How is the heat of science transmitted in primary school, and the second volume of science How is h

1. Definition: Heat conduction is a heat transfer phenomenon when there is no macroscopic movement in the medium, which can occur in solids, liquids and gases, but strictly speaking, only in solids is pure heat conduction, and even if the fluid is at rest, it will also produce natural convection due to the density difference caused by the temperature gradient, therefore, heat convection and heat conduction occur at the same time in the fluid.

Thermal convection, also known as convective heat transfer, refers to the heat transfer process caused by the relative displacement of particles in the fluid, and is one of the three ways of heat transfer.

Thermal radiation, the phenomenon in which an object radiates electromagnetic waves due to having a temperature. One of the 3 ways in which heat is transferred. All objects with temperatures above absolute zero can produce thermal radiation, and the higher the temperature, the greater the total energy radiated and the more shortwave components will be emitted.

2. Difference: Heat conduction is the process of transferring heat energy from high temperature to low temperature; Thermal convection is the process by which heat is transferred through a flowing medium; Thermal radiation is the phenomenon in which an object radiates electromagnetic waves due to its temperature and is the only way to transfer heat in a vacuum.

How heat is transferred.

Teaching Objectives] Scientific Concepts:

1. Heat will always be transferred from the higher end (object) to the lower end (object);

2. The transfer method of heat transfer from one object to another, or from one part of the object to another, through direct contact, is called heat conduction.

Process & Methodology:

1. Design experiments to observe the process and direction of heat conduction.

2. Use words or diagrams to record and communicate observed phenomena about how heat is transferred.

Emotions, Attitudes, Values:

1. Maintain an active interest in observing heat transfer.

2. Experience the joy of success through positive thinking and **.

Teaching Focus】 Design experiments to observe the process and direction of heat conduction.

Teaching Difficulties] By analyzing the common characteristics of the heat conduction process, we can understand how heat is conducted.

Teaching Preparation] Prepare for each group: iron frame; Iron wire (steel bar), hot water; Matches, metal discs, alcohol lamps, candle oil, petroleum jelly, etc.

Teaching process] Introduction: Heat the metal strip with an alcohol lamp, and the metal strip will become very hot and hot after a while. Can we explain this change? How do you think heat is transferred?

Students exchange their ideas.

1. Observe and study how heat is transferred in metal bars.

1. Soak one end of the metal strip in very hot water, and touch the part of the metal strip that exposes the water.

2. Communicate the feeling of hands.

3. Tell me how heat is transferred in a metal bar.

4. Teacher: According to the material, is there a way for us to "see" or feel the transfer of heat in a solid?

5. Discuss the experimental plan in groups.

6. Exchange experimental schemes: which methods can be used for experimental research.

7. Students will practice experiments and communicate their findings.

In the experiment, the teacher should grasp two development directions: observe and record the sequence of matches falling and the relationship between the falling time and the distance between the matches, so as to describe the characteristics of heat in the direction and speed of transmission. ）

8. Summary: Through experiments, we have found that heat is always gradually transferred from the hotter end to the colder end.

2. Transfer of heat in metal sheets.

1. Heat the center of the metal disc coated with wax, observe the melting of the wax, and speculate how the heat is transferred in the metal sheet

2. How to make the heat transfer on the metal sheet "visible"?

3. The group designs the experimental plan.

4. Exchange experimental schemes: which methods can be used for experimental research.

5. Carry out experimental observation activities in accordance with the textbook experimental design device diagram.

6. Communicate the findings in the experiment.

Let students experience it as much as possible to develop their understanding of heat transfer, with a special emphasis on safety).

Board design: how heat is transferred.

Warmer Cooler temperatures.

Hot Teaching Postscript:

3 Heat absorption and heat dissipation.

1. Teaching Objectives.

1) Process and Method:

1. Able to complete comparative experiments on the heat absorption and heat dissipation performance of different objects.

2 Be able to design experiments on the effect of object color on heat absorption and heat dissipation.

2) Knowledge and Skills:

1 Know that different objects have different properties to absorb heat and dissipate heat.

2 Know that dark-colored objects absorb heat faster than light-colored objects.

3) Emotions, Attitudes and Values:

1 Realize that conclusions need data to validate.

2. Be aware that many of the phenomena around you contain scientific truths.

3. Have a serious, meticulous and strict working attitude, and be willing to cooperate with others to complete experimental tasks.

2. Teaching Preparation:

1 cup, thermometer, water, sand, record sheet, black and white paper cups, balloons of different colors, etc.

3. Teaching process:

a) Review Introduction:

In class, we looked at several ways of heat transfer. Is the heat absorption and heat dissipation performance of different objects the same (2) Self-directed learning:

1 Study whether the heat absorption and heat dissipation properties of different objects are the same.

1) Teachers and students discuss the following questions:

a Which objects in our lives absorb heat quickly and dissipate heat quickly?

b Which objects are slow to absorb heat and dissipate heat?

c Which objects absorb heat slowly and dissipate heat quickly?

d Which objects absorb heat quickly and dissipate heat slowly?

2) Do you know how well water and sand absorb heat and heat?

3) Student** heat absorption and heat dissipation of water and sand.

4) Discuss in groups how the experiment should be done. There are several issues that should be noted:

a What same conditions need to be controlled? What materials are needed? What should be the division of labor within the group? How do I do the experiment?

5) Students are grouped into experiments

a There should be as much water as sand, and the same cups.

b Observe in sunlight for 10 minutes to measure the temperature changes of water and sand; Then observe in a cool place for 10 minutes to record the temperature changes of water and sand.

c Record the results of the experiment in ** of P78.

d Complete the remainder of P78.

6) Report and exchange.

7) Draw conclusions.

a Sand absorbs heat quickly and dissipates heat quickly. Water absorbs heat slowly and dissipates heat slowly.

b Comparative experiments: Experiments like this in which a controlled comparison is performed under the same conditions are called comparative experiments.

2 When studying objects of different colors, do they have the same heat absorption and heat dissipation properties?

1) Students discuss how to study the problem.

2) Methods for students to report their research. It is recommended to study from the following aspects:

a．**；b. Design experiments;

c. Conduct experiments;

d Record data, analyze data, and draw conclusions.

3. Consolidate the application: 1. Where are the heat absorption and heat dissipation properties of objects used in life?

Reflection on Teaching:

(Textbook Edition) Lesson Plan for Grade 5 Science.

Unit 2. Hot.

1. Brief analysis of teaching materials:

There are two main activities in this lesson.

The first activity is: the transfer of heat in a metal bar. First, students can feel the heat transfer in the metal strip by touching it with their hands, and then judge the process and direction of heat transfer.

On this basis, an intuitive experiment was designed to observe the process and direction of heat transfer in metal strips, with the aim of clearly seeing the direction and process of heat transfer with the eye.

The second activity is the transfer of heat in a sheet of metal. In this session, students will be able to observe the phenomenon of heat conduction in more depth.

Based on the experience of daily life, students tend to think that heat conduction is a linear process, and the above experimental observation activities seem to strengthen their understanding of this. Is this really the case with heat conduction? The textbook is designed to observe the heat transfer in the metal sheet, which not only broadens the students' thinking, but also enables the students to have a new understanding of heat conduction, and more deeply understand that heat is transferred from a place with a high temperature to a place with a low temperature.

From the perspective of the arrangement of the teaching materials, students can accurately conclude that heat is transferred from a place with a high temperature to a place with a low temperature after experiencing the first activity, and the purpose of the second activity is to make students observe more deeply and make them have a more comprehensive knowledge and understanding of heat transfer. The process and direction of heat transfer on metal sheets is an extension of the first experiment, which further deepens students' understanding of heat conduction from point to surface.

2. Teaching Background:

How Heat Is Transferred" is a continuation of the content of Lesson 5 "Does Metal Expand and Contract", in Lesson 5, when experiencing the heating of metal objects by alcohol lamps, students have already initially felt the phenomenon of heat transfer. At the same time, the conclusion of heat transfer is applied in the seventh lesson "Heat Transfer Competition", so from this point of view, in the lesson "How Heat is Transferred", students will observe the process and direction of heat transfer in metal strips through experiments under the guidance of the teacher. Then, the observation results are comprehensively analyzed, and the common characteristics in the heat conduction process are analyzed, so as to form a superficial understanding of how heat is transmitted, which has the role of connecting the previous and the next in this unit.

3. Instructional Design:

Teaching Objectives: (1) Scientific concepts:

1. Heat will always be transferred from the higher end (object) to the lower end (object);

2 Heat transfer is called heat conduction in which heat is transferred from one object to another, or from one part of an object to another, through direct contact.

Scientific Vocabulary: Heat Conduction.

2) Process and Methodology:

1. Design experiments to observe the process and direction of heat conduction.

Scientific Method: Experiment, Observation.

c) Affective Attitudes and Values:

1. Maintain an active interest in observing heat transfer.

2 Experience the joy of success through positive thinking and **. Core values: Willing to communicate, listen carefully, respect others, and obtain valuable information.

"How Heat is Transmitted" classroom teaching record.

Coaching: Zheng Congmo.

Teaching process: 1. Observe and question, and introduce new lessons.

Teacher: Students, we have to deal with many hot objects every day in our life and study, can you give an example?

Sheng: I found that when I cook rice, the lid and handle of the pot get hot.

Sheng: I found that when I boiled water, the water slowly got hotter and eventually boiled.

Teacher: The board book topic "How is heat transmitted?"

2. Experiments, breakthroughs in key points.

1) Experiments on heat propagation in solids.

Teacher: First of all, please observe the materials that the teacher has prepared for each group.

Teacher: What do you want to study with these materials?

Sheng: I want to study how heat is transferred in wires?

Teacher: If you were asked to heat with an alcohol lamp, how do you think the heat would be transmitted?

Teacher: Can you make your guesses?

How heat is transferred.

"Thermal Expansion and Cold Contraction" is the content of the "Cold and Heat" unit in the second volume of the third grade of the original textbook "Science". A total of 4 activities are designed in the textbook: 1. Observation of the volume change of water; 2. Do other liquids also expand and contract? 3. Whether the air expands and contracts coldly; 4. Observe the thermal expansion and contraction of solids (copper balls).

There are 2 class hours for the 4 activities, and the first lesson is mainly to solve the first class.

For the first and second two activities, the second lesson will be solved.

Three and four two activities.

The new textbook puts this content in the second volume of the fifth grade, and separates the first two activities in the text "Thermal Expansion and Cold Contraction" to form the current lesson "Thermal Expansion and Cold Contraction of Liquids", which has a clearer structure.

The first activity, Observing the Volume Change of Water, is to guide students to improve the experimental setup according to the problems encountered during the observation, and to use this experimental apparatus to explore the thermal expansion and contraction properties of water.

The second activity – do other liquids also expand and contract? Through this device, more other liquids can be studied to see if they are also hot and cold contraction, with the aim of developing students' activities in a broader direction, and at the same time cultivating a rigorous scientific attitude. Finally, the scientific concept that "many liquids have the properties of thermal expansion and cold contraction" is derived.

Design ideas. Science is in life, and when we talked, I chose a life situation: the phenomenon of milk overflowing when milk is hot. On the one hand, it lays the foundation for this lesson, and on the other hand, it guides students to pay attention to ordinary life phenomena.

When observing the change process of the volume of water when it is heated and cold, the phenomenon is not obvious by using the experimental device in the previous lesson, so that the students feel that it is very necessary to design a good experimental device, and on this basis, the students are very willing to participate in the discussion of improving the experimental device.

After discussing and improving the experimental device, the enthusiasm of the students' experiments has been completely mobilized, and the change in the volume of water when it is heated and cooled has also been natural. In this experimental observation and communication activity, students will really find that the volume of water expands when it is heated and shrinks when it is cold, which we call the thermal expansion and contraction of water.

Water expands and contracts in heat, but what about other liquids? Such a problem extension reflects the rigor of thinking. After observing the thermal expansion and contraction of water, the tissue of other liquids such as: milk, oil, soy sauce, vinegar, tea, etc. Learn more about the expansion and contraction of liquids.

At the end of the lesson, it is considered that after studying the thermal expansion and contraction of liquids, the subsequent arrangement of the textbook is to study the thermal expansion and contraction of gases. How to achieve knowledge transfer before and after? I deliberately arranged the last "fountain experiment", using the students' devices, with slight modifications, to make the red water spray more obvious.

Students will think to themselves: why didn't we spray so much when we did it ourselves? How is it going to happen?

Have students leave the class with questions. In the next lesson, the teacher can also analyze this phenomenon and enter the ** of air thermal expansion and cold contraction.