"Ear and Hearing" PPT courseware

Description

"Ear and Hearing" PPT courseware

Part One: Knowledge Review:

1. Sound is produced by the vibration of objects.

2. Sound propagation requires a medium, and sound cannot be transmitted in a vacuum.

3. Different materials propagate sound at different speeds.

4. Sound is a kind of wave, we call it sound wave.

So how is the sound heard by the ears?

The ear is divided into three parts: ____, _____, and _____.

The outer ear includes: ______, _____.

Auricle: ______ sound waves;

External auditory canal: _____ sound waves.

Placing your hands in an arc behind your ears will make the sound louder than it originally was.

The auricle has the function of collecting sound waves in the air.

Ear and hearing PPT, part 2: 2. The formation of hearing

hearing loss

(1) As age increases, hearing becomes less sensitive. (Natural causes)

(2) Damage to hearing organs. (deaf)

Based on the formation process of hearing, what are the possible causes of hearing impairment?

A. Damage such as damage to the tympanic membrane or ossicles (conductive disorder)

B. Damage to the cochlea or auditory nerve conduction system (neurological disorder)

Problem thinking

Deafness - unable to hear anything.

What are the causes of "deafness"?

①Conductive deafness: tympanic membrane rupture, auditory ossicle damage, etc.

1. Acute otitis media is not treated in time

2. Loud sounds or slaps create a pressure difference between the inside and outside of the eardrum.

3. Diving too deep

②Nervous deafness: damage to the cochlea, auditory nerve, auditory center, etc.

Related auditory nerve damage, drug effects, etc.

Ear and Hearing PPT, Part 3: Characteristics of Sound

(1) Tone

The pleasant sound is called______

The pitch of the sound is called ______

What determines the pitch of a pitch?

Activity: What determines the pitch of a pitch?

1. Take a plastic ruler and run it across the teeth of the wooden comb, one time faster and one time slower. Can you tell the difference in the sounds they make?

2. Press a ruler firmly on the table and use your hand to move the end that extends outside the table. Change the length of the ruler extending from the table and repeat the above experiment. Look carefully, what do you find? What are the different sounds produced by rulers extended to different lengths?

Conclusion: The faster an object vibrates, the higher the pitch.

The number of times an object vibrates in 1 second is called _____;

The unit of frequency is _____, abbreviated as Hz, symbol ___.

The faster an object vibrates, the ___ the frequency and the ____ the pitch.

Therefore, the pitch is related to the _____ of the sound-emitting body's vibration.

(2) Loudness

The subjective perception of sound intensity by people is called _____.

Conclusion: For the sound emitted by the same sound source, its loudness is related to the ________ of the sound source and the _____ distance from the sound source. Of course, different people experience sound differently.

The unit of loudness of sound is _____, and the symbol is ____.

Ear and Hearing PPT, Part 4: Practice

1. "Soprano singer" and "bass singer", the "high" and "low" here refer to ()

A. High or low pitch B. Good or bad timbre

C. Loudness D. Possible

2. The sound-emitting body is vibrating, but we don’t hear the sound. The reason is ( )

A. There is no medium for transmitting sound

B. Sound is ultrasonic wave

C. Sound is infrasound wave

D. All of the above are possible

Keywords: Zhejiang Education Edition seventh grade science PPT courseware for the second volume free download, ear and hearing PPT download, .PPT format;

For more information about the "Ear and Hearing" PPT courseware, please click on the Ear and Hearing ppt tab.

"Ear and Hearing" PPT:

"Ear and Hearing" PPT Part 1 content: 1. The structure of the ear Understanding the structure of the ear The outer ear includes: auricle, external auditory canal The middle ear includes: tympanic membrane, tympanum, ossicles (Eustachian tube) The inner ear includes: semicircular canals, vestibule, and cochlea. .. ... ... Ear and HearingP..

File Info

Update Time: 2024-09-06

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

Preview