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Lecture notes on "the speed of movement" in eighth grade physics

As an excellent teacher, it is often necessary to write a lecture, which is helpful to accumulate teaching experience and continuously improve teaching quality. So how should I write a speech? The following is the lecture notes of the eighth grade physics "The Speed of Motion" that I collected for reference only. Let's have a look.

First of all, talk about textbooks.

1. The position, function and analysis of teaching materials

The speed of movement to be talked about in this lesson is to further understand the movement on the basis of learning the knowledge of mechanical movement. This lesson is not only the deepening of the description of motion, but also the basis of studying Newton's first law, which plays a role in connecting the past with the future. The concept of speed is the most basic concept in middle school physical kinematics. If you understand and master the concept of speed, you can solve simple real life problems with what you have learned. Therefore, this lesson occupies an important position in this chapter.

In the teaching process, teachers should guide students to experience and analyze the speed of object movement by comparing time under the same movement distance; When the movement time is the same, the speed of the object can be judged by comparing the movement distance; When the distance and time of movement are different, we can judge the speed of an object by comparing the distance it moves in unit time, so as to understand and establish the concept and unit of speed, and master the conversion of speed unit through simple calculation of formulas; Through real life examples, we can understand the difference between uniform linear motion and variable linear motion, and the concept of average speed.

2. Analysis of learning situation

Speed is an abstract physical concept, which is limited by students' knowledge level and understanding ability and cannot be discussed comprehensively and concretely. Therefore, in teaching, according to the actual situation of our students, I appropriately reduce the teaching gradient, pay attention to basic teaching, and try to make use of physical demonstrations and multimedia courseware to make the teaching image intuitive. Each knowledge point starts from the familiar life phenomenon of students and forms a concept through analysis and induction, so as to better help students understand and master it. Only in this way can students learn something in class and enjoy the happiness of acquiring knowledge, thus stimulating students' interest in learning physics.

According to the above situation, I have set the following teaching objectives:

Second, talk about teaching objectives

1. Knowledge and skills:

(1). The motion of an object can be described by speed.

(2) The speed formula can be used for simple calculation and conversion between speed units.

(3) Know the concept of uniform linear motion

2. Process and method:

(1). Having experienced the process of observing physical phenomena, I can simply describe the main characteristics of the observed phenomena and have preliminary observation ability.

(2) Being able to use the knowledge learned to solve simple practical problems, and having the preliminary ability to analyze and solve problems.

3. Emotional attitudes and values:

(1). Feel the beauty brought by the combination of science and art, and be curious about science.

(2) In the process of solving problems, you have the confidence and determination to overcome difficulties and experience the happiness of overcoming difficulties and solving physical problems.

Third, talk about the key points and difficulties in teaching.

Key points:

1. The process of establishing the concept of speed.

2. Understand and master the concept of speed

Difficulties:

1. Conversion of speed units

2. Make a simple calculation by using the speed formula.

Let me focus on the teaching process.

Fourth, talk about the teaching process

This lesson will begin with the following links:

Creating scenarios-introducing new lessons-wonderful stories-observing and comparing-forming concepts-applying new knowledge-strengthening and consolidating-experiencing success-summing up.

1. Create scenarios and introduce new courses.

Using multimedia to play sports video materials.

Guide the students to observe carefully and find the question: What do the objects in the video have in common? Are the sports the same? Organize students to discuss and analyze, and draw the conclusion that all the objects in the video are moving, some are moving fast, and some are moving slowly. Then, a new question is raised: how to describe the speed of object movement?

In this way, by analyzing the common sports examples in life, the video leads to the teaching problems to be solved, which is convenient for students to easily integrate into the classroom atmosphere, so as to mobilize students' enthusiasm and stimulate their curiosity.

2. The story is interesting, and the concept is formed through observation and comparison.

Using multimedia to play the cartoon "Tortoise and Rabbit Race"

Ask questions, students think and discuss: Who ran faster at first? What is the basis of judgment? Who does the referee think runs faster in the end? What is the basis of judgment?

Stimulate students' interest in learning with short stories, activate the classroom atmosphere, let students speak freely and actively participate, cultivate students to observe, think, analyze, compare and discuss with each other, fully return the classroom to students, let students draw conclusions from their own analysis, comparison and discussion, let students experience the process of observing physical phenomena, and describe the main characteristics of observed phenomena, and also exercise students' language expression ability and analysis and generalization ability.

Students found a way to compare the speed of objects through communication and discussion: at first, rabbits ran fast because they ran a long distance at the same exercise time. Finally, the referee thought that the tortoise won the game because the distance was the same and the tortoise spent less time in the whole game.

Based on this, this paper summarizes two methods of object motion speed, and puts forward a new question: if the distance and time are different, how to compare the speed of object motion?

In this way, through observation, guidance, analysis, hierarchical questions, and gradually deepen the way to organize teaching. Through a series of purposeful activities such as "seeing", "thinking" and "speaking", students' ability to observe, think and analyze problems is cultivated, so as to realize the teaching goal of physics education.

Statement: The school's 100-meter champion score is 12s, while the 24 th Olympic Games' 10,000-meter champion score is 28min. How to compare their speed of movement?

Teachers keep asking questions, guiding students to arouse doubts and thinking step by step, and enlightening students' wisdom with heuristic teaching, so that students can draw a conclusion through drills: they can compare the distance they pass in 1 second or 1 minute, get what the unit time is, draw and understand the physical meaning of speed, thus gradually establishing the concept of speed, and let students rise from perceptual knowledge to rational height, and gradually understand the problems of physical research.

According to the definition of speed, we can directly get the calculation formula and unit of speed and its symbolic meaning, and convert the unit.

When explaining unit conversion, students should be guided to gradually deduce the conversion relationship between meters/seconds and kilometers/hours according to time units and length units, so that students can gradually understand and understand how units are converted, instead of memorizing them blindly. Physics stresses understanding. Learning to understand the memory, only by mastering the learning methods, can we change with constancy.

3. Apply new knowledge, strengthen consolidation and experience success.

Using multimedia to show examples:

Example 1: Jones won the gold medal in the women's 100-meter dash with a time of 10.75 seconds. Please use your knowledge to calculate the sprint speed of American track and field athlete Jones.

Solution: v = s/t =100m/10.75s = 9.30m/s.

A: The speed of American track and field athlete Jones in the 100-meter dash is 9.30m/s.

Example 2: Example: Wuzhishan to Haikou. The distance is 220 kilometers. A car goes from Wuzhishan to Haikou. How many hours can this car reach Haikou at a speed of 55 km/h?

Known: S=220Km, v = 55km/h.

Question: t

Solution: according to the formula v=s/t

T = signal-to-noise ratio

= 220km/55km/h

=4h

This car can reach Haikou in four hours.

Example 3: On July 2+September 12, 2065438, China's elite athlete Liu Xiang broke the world record of 1 10 meter hurdles held by colin jackson in golden league in Lausanne in 12.88 seconds. What is the average speed of this record? If the speedometer of a moving motorcycle indicates 30km/h, which speed is higher?

Solution:

Using the formula v=S/t, the speed of Liu Xiang is calculated as follows

v 1 = S/t = 1 10m/ 12.88S = 8.54m/S

What is the speed of the motorcycle?

V2 = 30km/h = 30/3.6m/s = 8.3m/s.

So the speed of Liu Xiang is higher than that of motorcycles.

The first problem is the direct application of the formula V = S/T, which is relatively simple and easy to understand, so that students can solve it smoothly and feel the joy of success. The second question is written according to the local actual situation in Wuzhishan City. The purpose is to understand how the formula is deformed and learn the application of the deformed formula. At the same time, it also makes students feel that the application of physics in life is everywhere, which is conducive to cultivating students' awareness of application. The third problem involves the conversion between units, which is a little difficult to teach, in order to let students understand the physical meaning of speed.

Through the explanation of these three exercises, let students develop the good habit of analyzing the meaning of the questions first and then standardizing the problem solving.

Introduction of uniform linear motion;

Using multimedia to show the content of discussion, let students know that stroboscopic photography is also a method to study physical problems, and guide students to analyze the difference between the motion States of two objects in two pictures, and then get what is uniform linear motion through comparative analysis.

At the same time, it is pointed out that uniform linear motion is the simplest mechanical motion, which is hardly seen in daily life because it is an idealized motion. Sometimes, in order to study problems and simplify physical problems, we will approximately regard some motions as uniform linear motions.

The teacher briefly introduces variable speed movement and average speed, so that students can pay attention to distinguish between average speed and average speed.

Classroom exercises:

1, unit conversion:

(1)2 1.6 km/h = _ _ _ _ m/s

(2) 5m/s = _ _ _ _ km/h

2, the car driving on a straight road, 1 min through the distance of 1800 m, the speed of the car is ().

1800 m/s

summary

Finally, ask questions to guide students to summarize the main contents of this section, so that students can develop the good habit of learning first and then summarizing, and cultivate and exercise their language expression ability.

Verb (abbreviation of verb) oral teaching method and learning method

Teaching methods: heuristic teaching, observation and comparison, multimedia demonstration.

In order for students to establish correct physical concepts, we should follow the law of human cognition, that is, from perceptual knowledge to rational knowledge, which determines that the teaching of physical concepts should attach importance to intuition, that is, teaching physical concepts on the basis of intuition. This lesson mainly starts from two aspects: one is to understand the concept of speed and the difference between uniform linear motion and variable linear motion by using students' life experience and observing and comparing actual cases in life. Second, through multimedia courseware, students have an intuitive sense of understanding, combined with heuristic teaching methods, so that students can observe physical phenomena, engage in positive thinking activities, and form concepts through comparison, analysis and generalization.

Learning methods: observation, experimental discussion, comparison and induction, and improvement in practice.

The teaching process of this course is mainly based on students' observation and experiment, supplemented by teachers' analysis and teachers' problem analysis. In teaching, teachers guide students to observe purposefully by listing familiar examples, and gradually summarize the concept of speed.

First of all, multimedia courseware can better concentrate students' attention to observe and analyze phenomena. It is more convenient to compare and summarize, and improve students' ability of analysis and generalization. Secondly, in the teaching process, we should pay attention to respecting students' "subject" status and try our best to make students think, speak, do and practice. Through practice, we can learn to use the speed formula for simple calculation and conversion of speed units. Thirdly, by doing experiments, we can deepen our understanding of the physical meaning of speed.

Sixth, talk about blackboard design.

In order to reflect my teaching goal and make it easy for students to understand, my blackboard writing design is as follows:

velocity of movement

First, speed:

The physical meaning of 1. speed: it indicates the speed of the object.

2. Definition of speed: Speed is equal to the distance traveled by a moving object in unit time.

3. Calculation formula of speed:

v=s/t

Commonly used unit: kilometers per hour (km/h)

Conversion relation:1m/s = 3.6 km/h.

Second, uniform linear motion:

1. Definition: The uniform motion of an object along a straight line is called uniform linear motion.

2. average speed formula: v=s/t

Seven, homework layout:

1. 1 m/s = _ _ _ _ _ km/h

72 m/s = _ _ _ _ km/h

10m/s = _ _ _ _ km/h

15km/h = _ _ _ _ m/s

2. The walking speeds of Party A, Party B and Party C are 3.5 km/h, 64 m/min and 1m/s respectively. What is the speed relationship between them?

3. The car traveled at a speed of 25m/s for 2 hours, and the distance traveled during this time was _ _ _ _ _ _ _ _ km.

4. The speed of sound propagation in the air is 340 m/s. When a person shouts at a mountain 425 meters away, the time to hear the echo is ().

a . 1.25s b . 0.625s c . 0.8s d . 2.5s

Eight, the effect evaluation:

Through the study and discussion of teachers and students in this class, students can basically master the speed formula and its deformation, and can use speed to judge the speed of object movement; Students also learned to find physical problems from life, and can use what they have learned to solve such problems, so that physical knowledge can be effectively applied to life.