"Occurrence and Propagation of Sound" PPT courseware

Description

"Occurrence and Propagation of Sound" PPT courseware

Part One: Experiment

1. Get a rubber band, a steel ruler, and a pen cover, and try to make them make sounds.

1. When the rubber band and steel ruler stop vibrating, can you still hear the sound?

2. Place two fingers gently on your throat and make a sound.

①When you make a sound, you feel that your throat is _________.

②At this time, _________ is actually vibrating.

What characteristics do objects that produce sounds have in common?

in conclusion

Sound is produced by the vibration of objects

Occurrence and propagation of sound PPT, Part 2: Conditions for sound propagation

How does sound travel from the source to the human ear? What are the conditions for the propagation of sound?

①Put two desks close together, one student knocks on the desk, and the other puts his ear close to the other desk. Can you hear the knocking sound?

Question: What object is this sound transmitted by?

Conclusion 1: Sound can propagate in solids.

② Put the two desks away, one student knocks on the desk, and the other puts his ear close to the other desk. Can you hear the knocking sound?

Question: What object is this sound transmitted by?

Conclusion 2: Sound can propagate in gas.

Conclusion: Vacuum cannot propagate sound, and the propagation of sound requires matter. In science, such a substance is called a medium.

The occurrence and spread of sound PPT, the third part: thinking:

1. On the moon, when astronauts talk face to face, can they hear the sound? Why?

2. Many science fiction movies have scenes of war in space. Do you think explosions can be heard in space?

In what form does sound propagate in the medium?

The sink contains calm water with a cork floating on the surface. Use your pencil to tap somewhere on the surface of the water rhythmically.

Question 1: What phenomena will appear on the water surface?

Question 2: How does the cork move?

Place a candle in front of the speaker and when a strong sound comes from the speaker

Question 1: What will happen to the speakers?

Question 2: What will happen to the candle flame?

The occurrence and propagation of sound PPT, part 4: the speed of sound propagation

1 Explain why the team members have to listen with their ears close?

For example: Shen Kuo of the Northern Song Dynasty recorded in his book "Mengxi Bi Tan": During the march and camping, the soldiers slept on the ground with cowhide quivers as pillows, and they could hear the sound of the enemy's horse hooves early in the night. Why is this?

The speed of sound propagation in solid objects is greater than the speed of propagation in air. Therefore, a person can detect the enemy in time by sleeping on the ground with his ears attached to the quiver.

2: There is a very long tap pipe with water. One person knocks on one end of the pipe, and another person puts his ear to the other end. Theoretically, how many times should he hear the sound?

Occurrence and propagation of sound PPT, Part 5 content: Classroom exercises:

1. As the saying goes: The sound of wind, rain, and reading are all in your ears. Among them, the sound of wind, rain, and reading are the sounds produced by ___, _____ and the vibration of objects respectively. These sounds are transmitted in the form of _____ through _____ matter.

2. "The little bee buzzes and flies east and west. How does the bee make a cry? When the bee stops on the flower to collect nectar, can you hear the buzzing sound? Why?

3. What is the reason why astronauts need to use electronic communication equipment to communicate after landing on the moon?

4. As shown in the picture, if you place the sounding tuning fork close to the ball hanging on the line, you will find that the ball bounces away many times. This phenomenon indicates __________. If this experiment were carried out on the surface of the moon, what would you observe?

Keywords: Zhejiang Education Edition seventh grade science PPT courseware for the second volume free download, PPT download on the occurrence and spread of sound, .PPT format;

For more information about the "Occurrence and Propagation of Sound" PPT courseware, please click on the "Occurrence and Propagation of Sound" ppt tag.

"The Occurrence and Propagation of Sound" PPT download:

"Occurrence and Propagation of Sound" PPT Download Part One: Learning Objectives 1. Know that sound is produced by the vibration of objects. 2. Know that the propagation of sound requires materials. 3. Know the propagation speed of sound in the air... The occurrence and propagation of sound P..

"The Occurrence and Propagation of Sound" PPT:

"Occurrence and Propagation of Sound" PPT Part 1: Production of Sound Experiment 1: Place two fingers lightly on the throat, and then make a sound. What did you notice? __________ Experiment 2: Pulling the Tightened Rubber Band Do you hear the sound? _________..

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Update Time: 2024-09-28

This template belongs to science courseware Zhejiang Education Edition Seventh Grade Science Volume 2 industry PPT template

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