"The Utilization of Sound" Sound Phenomenon PPT Courseware Download

"The Utilization of Sound" Sound Phenomenon PPT Courseware Download

Part One: Guidance Design

Learning Point 1: Sound and Information

Read textbook P38~P39 and answer the following questions:

Question 1: What principle does sonar work on? What are its uses?

Answer: Sonar works based on the principle of echolocation. Sonar can be used to detect the depth of the seabed, the location of icebergs and reefs, etc.

Question 2: When performing a routine examination on a pregnant woman, ultrasound waves are emitted into her body. What information does the reflected sound waves carry? What are the other uses of ultrasound?

Answer: When ultrasound waves are emitted to pregnant women, the reflected sound waves carry information about the growth and development of the fetus. Ultrasonic waves can also be used for reversing radar, metal flaw detection, etc.

Learning Point 2: Sound and Energy

Experiment 1: Find a CD with a strong rhythmic song or piece of music, put it in the CD player, turn up the volume, put a piece of thin paper in front of the speaker, and observe the condition of the paper.

Experiment 2: Find an empty Coke bottle, remove the bottom, cover the opening with rubber film and tie it tightly. Knock the rubber membrane against the flame. Due to the vibration of the membrane, the compressed air and the squeeze of the air can blow out the candle flame (as shown in Figure 2-3-3).

think:

Question 1: What was the reaction to the piece of paper placed in front of the speaker in Experiment 1?

Answer: The piece of paper is constantly swinging. It is swinging due to the impact of the sound waves from the speaker.

Question 2: What blew out the candle flame in Experiment 2?

Answer: What blows out the candle flame is the sound wave produced by the vibration.

Question 3: What do the above two experiments show?

Answer: Sound waves have energy.

Question 4: What are the practical applications of ultrasonic energy?

Answer: Ultrasound can be used to clean objects. In medicine, ultrasound can also be used to crush stones in the body.

Utilization of sound PPT, part 2: application examples

Type 1 Sound energy transmits information

Example 1: All objects that make sounds are ________. As shown in Figure 2-3-4, the worker uses a screwdriver to check whether the internal operation of the motor is normal. This phenomenon shows that ________ can transmit sound; the sound can be heard to determine whether the motor is running normally.

Whether the internal operation of the machine is normal, this takes advantage of the property that sound can transmit ________ (optional "energy" or "information").

[Analysis]All objects that make sound vibrate. If the object does not vibrate, there will be no sound. Solids can transmit sound better than liquids and gases. Using a screwdriver to detect whether the internal operation of the motor is normal uses the property of sound to transmit information.

[Summary of rules]Sonar, B-ultrasound, life detectors and other instruments receive sound waves and display the information carried by the sound waves after processing. Examples of using sound to transmit information can be roughly divided into two categories: one is the sound waves directly emitted by objects carrying information; the other is the reflected sound waves carrying information.

Type 2: Acoustic energy transfer energy

Example 2 2017·Jiangxi Sound is produced by ________ objects. When people speak loudly in snowy mountains, because the sound can transmit ________, it may trigger an avalanche.

[Error-prone analysis]The nature of using sound to transmit information is to use sound to determine the characteristics, properties, position and other factors of an object, that is, to obtain certain information through sound. In the process of sound transmitting information, the structure, The shape and motion state will not change; the use of sound to transmit energy is to cause mechanical movement of objects or to break or reorganize them, that is, to use sound waves to achieve a certain purpose, which is manifested as changes in the motion state of the object or changes in shape and structure, etc.

PPT on the use of sound, part three: classroom feedback

1. Among the following items, sound can convey information ()

① The rumbling thunder indicates a possible heavy rain ② Sonar fishing ③ Ultrasonic gravel

④ B-ultrasound examination ⑤ Use sound waves to clean spectacle lenses ⑥ Use a stethoscope to understand the condition of the patient's heart and lungs

A． ①⑤⑥ B. ②③④

C. ③⑤ D. ①②④⑥

2. The following examples use sound to transmit energy ()

A． Using ultrasonic waves to detect flaws in metal workpieces

B. Teeth cleaning using ultrasonic waves

C. Doctor diagnoses patient with stethoscope

D. Ultrasonic blind guide helps blind people travel

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For more information about the PPT courseware "The Utilization of Sound Phenomenon and Sound", please click on the Utilization of Sound Phenomenon ppt ppt tab.

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