uk milf stella paris strips and wanks at babestation

Welcome to the original primary and secondary education resources network!

Review courseware of physics sound phenomenon

Time: 20:29:56, June 23, 2017 Courseware I want to contribute

Review courseware of physics sound phenomenon

The following small edition of stgeorgerx.com provides the review courseware of physics "sound phenomenon".

 Review courseware of physics sound phenomenon

What is sound Chapter 1 sound phenomenon (review)

1. Sound is due to the vocal body______ Produced. All the objects that make sound are in. Solid, liquid and gas can make sound_____ Stop, and the sound stops. Chapter one sound phenomena (review)

(Note: vibration will produce sound, but the sound may not be heard by people; If an object does not vibrate, it will never make a sound

2. Sound transmission Chapter 1 sound phenomenon (review)

(1) the transmission of sound needs, All solids, liquids and gases can be used as, Sound travels in the form of waves in a medium, which is called uuuuuuuuuu. Chapter one sound phenomena (review)

(2)_____ No sound. Chapter one sound phenomena (review)

(3) the speed of sound propagation in different media is different. The speed of sound propagation in solid is the fastest, followed by liquid, and gas is the slowest.

3. Sound waves can make objects vibrate and crush small stones, which indicates that sound has. Chapter one sound phenomena (review)

2 Characteristics of sound

The three elements of sound chapter one sound phenomenon (review)

(1) the three elements of sound refer to the sound_____ And. Chapter one sound phenomena (review)

(2) the tone refers to the sound, It's vibrated by objects_______ Determined; Loudness refers to the sound, It's vibrated by objects________ Determined; We can distinguish different people's voices by the sound. Chapter one sound phenomena (review)

(3)

Characteristics of sound

loudness

tone

timbre

influence factor

Vibrational

The distance of sound source

Vibrational

Material and structure of sound generator

sing another song

Change the force

Change the length, thickness and tightness of the voice

give an example

deafen the ear with its roar

As crisp as a silver bell

charm sb's ears

explain

1. Frequency: unit: 1

2. Amplitude: the amplitude of vibration

2. Complete the following inquiry experiments with a straight steel ruler:

(1) what is the relationship between loudness and amplitude of sound source?

(2) what is the relationship between the tone of the sound and the frequency of the source vibration?

(1) experimental method: put one end of the steel ruler on the table top, press it with your hand, and the other end sticks out of the table top (the same). For the first time, pull the steel ruler to make the steel ruler vibrate and sound; Pull the steel ruler for the second time to make the steel ruler vibrate and sound.

Phenomenon: the second time is louder than the first

Conclusion: the larger the amplitude is, the greater the amplitude is.

(2) experimental method: put one end of the steel ruler on the table top, press and hold it by hand, and the other end extends out of the table top (use the same size to move the steel ruler). For the first time, the steel ruler vibrates and makes sound. At this time, the steel ruler vibrates; Some of the second extension make the steel ruler vibrate and sound. At this time, the steel ruler vibrates.

Phenomenon: the second tone is lower than the first tone

Conclusion: the slower the vibration is.

3 Boring noise

1. Sources, hazards and control of noise Chapter 1 sound phenomena (review)

(1) the unit for classifying the sound intensity level is \\\\\\\\\\\\\\, It is indicated by the symbol "DB". Chapter one sound phenomena (review)

(2) the methods to reduce the noise are as follows: from the noise of the_________ And________ Three links to prevent and control. Chapter one sound phenomena (review)

2. From the perspective of environmental protection, the sound that affects people's normal study, work and rest belongs to noise.

Chapter 1 sound phenomena (review)

1. Because the frequency range of sound heard by human ear is U__ Hz_______ Hz, the sound within this range is called audible sound. People put the frequency below____ The sound at Hz is called "uuuuuuuuuuuuuuuuuu, Frequency higher than_____ Hz is called "uuuuuuuuuuuuuuuuuuuuuuuu.

2. Ultrasonic has the characteristics of, easy to obtain more concentrated sound energy. Application in life: sonar, B-ultrasound image, ultrasonic cleaner, ultrasonic welding machine

3. Infrasonic waves can travel far and easily. Infrasound waves of certain intensity can cause harm to human body.

Related articles: review courseware of sound phenomena in physics

one Junior high school physics sound phenomenon test questions

two Reflection on the teaching of sound phenomenon review

three Sound phenomenon of physics teaching plan

four Courseware of physics magnetic phenomena in junior high school

five Physics review courseware for junior three

six Review of sound phenomena in physics of grade eight

seven Examination questions of physical sound phenomenon in junior two

eight Review courseware of physical pressure in junior high school

daddy4k papa intelligent ne perd pas sa chance davoir des relations sexuelles avec ses fils nouvelle copine lustful old granny rides two cocks vrallure busty ebony beauty daizy cooper plays with her sex toys in virtual reality loan4k le banquier est pret a aider une fille si elle donne quelque chose en retour daddy4k sweetie and boyfriends old dad celebrate her birthday with sex