Sound phenomenon, people's education edition, the first chapter of physics in the second day of junior high school.

1, all vocal objects are in (). Sound can be transmitted by all (), () and () substances in the form of (). Sound cannot propagate in ().

2. The sound perceived by human ears is related to the () of the vocal body and also to the () of the vocal body.

3. "Soprano" and "Bass", in which high and low mean ()

A. Volume level B. Loudness level

C. The timbre is good or bad. D. It's all possible.

4, when the temperature is 65438 05℃, people shouted at the high wall, can hear the echo, the distance between people and the wall at least ().

A. 17m B. exceeding 17m.

C. less than 17m. D. not sure.

The first measurement of sound propagation speed in cast iron was made in Paris by the following methods: knocking a bell at one end of the cast iron pipe and hearing two kinds of noises at the other end of the pipe. The first time is from cast iron pipe, the length is 931m; The interval between two noises is 2.5 seconds. If the speed of sound in the air at that time was 340 m/s, find the propagation speed of sound in cast iron.

There is a mountain in front of the car. The car is driving at a constant speed of 54 km/h, and the car honks. Three seconds later, the driver heard an echo. How far is the car from the mountain at this time? How long does it take to get to the foot of the mountain? (At that time, the speed of sound in the air was 340m/s)

Practice answer:

1, vibration, solid, liquid, gas, medium, vacuum 2. Amplitude, distance 3. A4.B5.3908m/s

6.487.5 meters 32.5 seconds

Sound phenomenon synchronous test questions

Fill in the blanks

1. The vocalists are all there, and the objects that stopped vocalizing are all gone.

2. At15℃, the speed of sound propagation in the air is.

Sound can spread not only in the air, but also in the air.

The astronauts on the moon can only talk without electricity even if they are very close, because.

Fish can be attracted by their favorite sounds, which means they can also transmit sounds. Use of "earth phone"

The quality of being able to transmit sound.

If the echo reaches people's ears a few seconds later than the original sound, people can distinguish the echo from the original sound.

Second, multiple choice questions

1. The following statement about sound propagation is incorrect ().

A. Sound travels slower in solids and liquids than in vacuum.

B. The students heard the teacher's voice spread through the air.

C. Vacuum cannot transmit sound.

D. When playing a gong, to stop the gong, just press the gong face with your hand.

2. Can't spread sound is ().

A. vacuum wood air water

3. Compare the propagation speed of sound in seawater, iron pipe and air, and arrange it from big to small. What is correct is that

( )。

A. Sea water, iron pipes and air

C. air, iron pipes and seawater

4. In the 100-meter race, the referee's correct timing method is ().

A. start timing when you hear the starting gun. B. start timing when you see the smoke from the starting gun.

C. When you hear the last password issued by the starter, start timing. Watch the first runner start timing.

5. Among the following statements about sound, the correct one is ().

A. All vibrating objects make sounds.

B the distance that an object deviates from its original position during vibration is called amplitude.

C. the number of times an object vibrates is called frequency.

D the hearing frequency of normal people is between 20 and 20000 times per second.

6. There is an air steel pipe with a length of 100 meter. A student knocks at one end of the steel pipe, and B student can hear several noises at the other end of the steel pipe ().

A. One noise B. Two noises C. Three noises D. Four noises

Third, the calculation problem

1. The observer heard thunder 5.5 seconds after seeing the lightning. What is the distance between thunder and the observer?

2. 0.5 seconds after clapping, I heard the echo reflected from the opposite wall. What is the distance between people and the wall?

Ring the bell directly below the sea surface, and the bell will spread to the bottom of the sea and then reflect back to the sea surface. * * * After 2.0 seconds, it is known that the speed of sound in seawater is1500m/s. What is the depth of seawater?

Test paper answer:

Fill in the blanks

1. Vibration, vibration 2. 340 m/s 3. Liquid, solid 4. There is no air on the moon. Water, solid.

6.0. 1

Second, multiple choice questions

1.A 2。 A 3。 B 4。 B 5。 a、B、D 6。 D

Third, the calculation problem

1.1870m 2.85m 3.1500m

There is also an unanswered question:

1. Fill in the blanks (65438+ 0 for each blank, ***30)

1. During the dragon boat race, drums are heard from the drum surface.

2. In the following statements about sound, the physical meaning of each expression is:

(1) "You have a beautiful voice" is sound.

(2) "Thunder is deafening" means sound.

(3) "Children scream" refers to sound.

3. Put a lighted candle in front of the horn. When there is a strong sound in the loudspeaker, you can see candles, which means that there are sound waves.

There is a beautiful piano sound in the distance, which is made by the steel wire of the piano. Constantly but louder, the sound of the piano was introduced to people's ears. In the air of 15℃, the propagation speed of piano sound is.

5. In terms of noise control measures, signs as shown in the figure can be seen in some places, mainly to reduce noise; When there is noise outside the classroom, the doors and windows are closed to reduce the noise.

6. The frequency range of sound waves that the human ear can hear is usually in. Monitoring and controlling ocean waves can help to reduce its harm and can be used to predict earthquakes and typhoons.

7. People's arms can vibrate up and down to form waves, and people's ears can (or may not) hear this sound.

8. In ancient times, people often used the method of "lying down and listening" to judge whether there were horses. This is an application.

... knowledge

9. Playing the "1" key in B key on the piano is more frequent than playing the "1" key in C key.

10. The frequency of international standard sound is 440Hz, and its physical meaning is.

1 1. Playing the same key with different dynamics makes different sounds because playing different keys with the same dynamics makes different sounds because playing different instruments with the same dynamics makes different sounds.

12 sound. 0dB. Generally speaking, people's pulse increases with the increase of noise intensity, so noise is called "."Noise above decibel will damage people's hearing.

13. Bats fly and prey in the dark by receiving their own echoes.

14. In modern cities, indicating devices are often set beside main roads. There are constantly changing numbers flashing on it, numbers

Followed by the symbol "dB". The function of this device is.

15. A and B in the figure are two sound waves.

Figure, from which we can know that figure is the waveform of music.

16. A muffled thunder makes people panic; It seems that someone is playing the Hu Qin in the distance; A sharp scream immediately quieted the noisy people. The characteristics of sound emphasized by the above three sound phenomena are, in turn.

17. There is a scene in the science fiction movie: a spaceship is in distress in space and another spaceship is going to rescue it.

On the way, I suddenly heard the huge explosion of the ship in distress, and then I saw the inner light of the explosion. Please give it to the director.

Point out two scientific mistakes in this scene:

.

Second, multiple-choice questions (24 points)

18. Of the following statements about sound, the correct one is ().

A. All vibrating objects make sounds.

B the distance that an object deviates from its original position during vibration is called amplitude.

C. the number of times an object vibrates is called frequency.

D. The hearing frequency of normal people is between 20 and 20,000 times per second.

19. There is a hollow steel pipe with a length of 100 meter. A student knocks at one end of the steel pipe, and B student can hear it at the other end ().

A. One echo B. Two echoes C. Three echoes D. Four echoes

20. The following statement about tone and loudness is true ().

A. high pitch means high loudness.

B. Low pitch means low loudness.

C. The word "Gao" in "Shout loudly" actually means loudly.

D "low" in "whispering" actually means low tone.

2 1. In the experiment of demonstrating the sound produced by object vibration, the sounding tuning fork was pressed on the foam ball under the suspension line, and the ball bounced off many times. In this experiment, the function of foam ball is ()

A. stop the vibration of the tuning fork as soon as possible

B, prolonging the vibration time of the tuning fork

C. amplify the tiny vibration of the tuning fork for easy observation.

D, repeatedly reflecting sound waves to form echoes.

22. Ultrasound has a wide range of applications. What does not belong to ultrasound application is () in the following cases.

A. ultrasound imaging B. sonar ranging C. speedometer D. decibel meter

20. About the role of amplifier, the following statement is correct ().

A. change the loudness B. change the tone C. change the timbre D. reduce the dispersion of sound

23. There is no echo in the cinema. The correct one of the following reasons is ()

A. the sound reflected by the wall cannot be separated from the original sound.

B. the wall is sound-absorbing, and most of the sound transmitted to the wall is absorbed.

C.this wall absorbs all the sounds.

D. None of the above statements are correct.

24. Bats can find insects to prey in the dark, which is ()

A. by ultrasound. Through the compound eye

C. with the help of infrared rays

25. About the spread of sound, the following statement is true ().

A. astronauts on the moon can hear each other's applause.

B. Sound can be transmitted through solids and gases, but not through liquids.

C the speed of sound propagation in the air is about1500m/s.

D. patrolmen usually put their ears to the railing to hear if there is a train coming in the distance.

26. In the ancient poem, "The teenager leaves home, the old man returns, and the local accent does not change." "The local accent hasn't changed" mainly means that it hasn't changed ()

A. sound B. loudness C. timbre D. dialect and dialect

27. When the train is drilling a cave, the sound of wheels rolling on the rails is compared with the sound of the train driving outside the cave ()

A. the voice is very low. B.the sound is ringing

C. the voice hasn't changed. D. the sound disappeared

28. The timekeeper standing at the finish line of the 100-meter race immediately started to time when he heard the gunfire at the start. It is measured that the running time of Li Ming 100 meter is 14.00 seconds and the temperature is 15℃, so the real running time of Li Ming 100 meter is ().

14.29 seconds

C. 13.7438+0 seconds D. Not sure.

29. Based on the principle of noise elimination ()

A. When the dense part and the sparse part of the sound wave just meet, they will reinforce each other.

B. When the dense part and dense part of sound wave just meet, they will cancel each other out.

C. When the sparse part and the sparse part of the sound wave meet, they will cancel each other out.

D. "Noise elimination" method is also called "active noise elimination technology"

30. The following things, do not belong to the sound source is ()

A. "Sonar" detects enemy submarines B. Shooting and flying in the dark C. Whistle hanging on the chest D. Arm vibration

3 1. The following sentence is incorrect ()

Rocket launch, airplane flight and the running of trains and cars will all form infrasound waves.

B. Volcanic eruption, meteorite falling, earthquake, tsunami, typhoon and lightning will all form infrasound waves.

C. low-frequency infrasound is harmful to human body.

D infrasound can travel far, and strong infrasound can circle the earth 2-3 times, but it is not easy to bypass obstacles.

32. As shown in Figure B 1-2, four identical glass bottles contain water with different water levels. Blow into the bottle mouth. If you can play the four scales of Dou (1), Ru Ai (2), Fan (3) and Fa (4) respectively, the corresponding bottle number of these four scales is ().

A. C, B, A and D

B.b, c, a and d

C.a, b, c and d

D.d、C、B、A

The fish that was about to bite the bait suddenly heard footsteps and ran away in horror. At this time, the main way for fish to receive sound waves is () B 1-2.

A. Earth-air-water-fish

C. Earth-water-fish

34. About the sound wave error ()

A. sound waves also exist in solids and liquids.

B. With the constant vibration of the tuning fork, density fluctuation is formed in the air and spreads to the distance.

C. Sound waves can not only make the eardrum of human ears vibrate, but also make other objects vibrate.

D. Sound waves can also travel in a vacuum.

35. When plucking the strings, you can hear pleasant sounds. Which of the following objects vibrates ()?

A. fingers B. strings C. air D. strings

Third, the experiment and design questions (2 points, 24 points, 4 points, ***22 points per grid)

35. As shown in Figure A 1-3, put a small bell in the glass cover connected to the air extractor. Please answer the following questions:

(1) Pump up the air in the glass cover gradually, and you will find it.

(2) If air is gradually introduced into the glass cover, it will be found.

(3) This experiment shows that.

36. In Figure A 1-4, Xiaoming and Xiaogang connect two paper cups with fine cotton thread to make a "earth phone".

(1) They can use "earth phone" to realize communication between l0m, which is evident.

(2) Speakers speak at the same distance and with the same loudness. If you connect the earth phone with a thin wire, you will hear a louder sound. This experimental phenomenon shows that:

(3) If another student holds a part of the line with his hand when using the earth phone, the listener will not hear the sound. This is because.

(4) When using the terrestrial telephone, if the line is not straightened and is in a slack state, the receiver can hear the other party's voice through the cotton thread (choose "Yes" or "No").

37. as shown in figure A 1-5, gently bite the upper end of the pencil with your teeth, tap the lower end of the pencil with your fingers, pay attention to the tapping sound, then open your mouth so that your teeth don't touch the pencil, and tap the lower end of the pencil with your fingers with the same strength as before. Comparing the two sounds, the differences are as follows:

(1) The main difference between these two sounds is different (optional: tone, loudness, timbre);

(2) What do you think you have learned from this experiment? A:

Please design an experiment with a thin piece of paper to prove that sound waves have energy. Briefly explain the practice.

39. How to estimate the speed of sound propagation in the air?

Equipment:

Steps:

40. On an outing, the students held a suburban dance. Because there is no musical instrument, Xiao Ming designed a soda bottle percussion instrument with soda bottles brought by his classmates and played beautiful music.

(1) What auxiliary equipment does Xiao Ming need besides soda bottles?

(2) What's the difference between bass bottle and treble bottle in design? Why?

4 1. Using a thin steel ruler and a table, please design the following two small experiments and briefly explain the experimental steps.

(1) It is proved that the loudness of sound is related to the amplitude of the sound generator.

(2) Explore the factors that determine the pitch. What do you think affect the pitch are:

. Design an experiment to verify your guess.

Four, calculation and short answer questions (24 points)

42. Why can you hear the buzzing of mosquitoes flying around, but you can't hear the sound of waving your hands back and forth?

43. What's the difference between tone and loudness?

44. What harm does the strong infrasound environment do to our life? Please write three related scenes.

45. Students in a middle school physics activity group consulted materials and got the speed of sound propagation in some substances (see the table below). An iron pipe long enough, exposed on the ground, filled with water. When the temperature is 20℃, a classmate in the group taps at one end of the iron pipe, and the classmate at the other end of the iron pipe can hear at most two taps. If the time from the last tap is 1.2s, then the length of this straight iron pipe is about m. ..

Material temperature (℃) speed (m/s)

Air 20 340

Water 20 1450

Pine 20 3320

Iron 20 4900

46. Someone shouted at a dry well. After 0.2s, he heard an echo and asked how deep the dry well was.

A student in Class 6, Grade 2 recorded the noise in the classroom as follows: Time: 031June1June 5438+02: 00 Location: Class 6, Grade 2.

Xiaohong and other students are watching the music appreciation played by Jiangsu Literature and Art Channel.

Xiao Huang is reading extracurricular books.

The pony is patting the ball in front of the podium.

Several students were sitting around arguing loudly.

(1) According to this classmate's record, for Xiao Huang, the noise is.

For Xiaohong, noise is.

(2) Under the background recorded by this classmate, please put forward suggestions or schemes (not less than two) to control classroom noise.

A device called "vacuum glass" (such as the wall of the house in the picture) is often used in modern buildings. Please use the sound knowledge you have learned to explain the advantages of this glass.