1. The following statement is true ()

A. As long as the object is vibrating, people will certainly hear the sound.

B. As long as you hear an object make a sound, it must be vibrating.

C. as long as people can't hear the sound, objects will not vibrate.

D. All the above statements are correct.

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

A. "Sonar" detected that the enemy submarine B. was flying in the dark.

C. Whistle hanging on the chest and arm vibration.

3. In the experiment of demonstrating that sound is caused by the vibration of an object, as shown on the right, the tuning fork that is making sound is pressed on the foam ball under the suspension line, and the ball bounces off many times. In this experiment, the function of the 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, amplifying the tiny vibration of the tuning fork to facilitate observation; d, reflecting sound waves for many times to form echoes.

Knock on one end of a long water pipe. If another person can hear three knocks by sticking his ear to the other end of the pipe, the medium from which these three knocks come is () in turn.

A. iron pipe, water and air B. water, air and iron pipe C. air, water and iron pipe D. water, iron pipe and air

5. The picture on the right shows the astronauts working outside the cabin. The dialogue between them can only be carried out by means of electronic communication equipment, but they can talk directly in the spaceship cabin. The reason is ()

A.there is too much noise in space. B. Space is a vacuum and cannot transmit sound.

C. it is more convenient to talk with communication equipment. D. sound can only spread near the ground.

6. In the following phenomena, it can be explained that sound can spread in liquid ().

A.light attracts fish into the net. The fish were scared away by the conversation on the shore.

C. hear the sound of the river flowing on the shore D. the roar of the waves hitting the coast

7. The following facts cannot clearly show that sound has energy ()

A. A vibrating horn can "blow out" the flame of a candle. B. Cars pass by on the road, and residents' windows hum along the road.

C. Wonderful music can cultivate people's minds. D. Use ultrasonic waves to break stones in the body.

8. The pitch of the sound depends on ()

A wavelength b, frequency c, amplitude d, sound wave propagation speed and timbre.

9. The loudness of the sound is determined by ()

A, the amplitude of the sound source; B, the frequency of the sound source.

C and d are determined by the timbre of the sound source, and d is determined by the above factors.

10. The drummer hits the drum hard to make the drum sound ()

A. pitch increase B. loudness increase C. timbre change D. none of the above statements are correct.

1 1. In the thunderstorm season, some children are afraid of thunder because it thunders ().

A. the frequency is very high. B. the range is very high. C. Loudness is very high. D. the tone is very high.

12. We live in a sea of sound, birdsong, running water and piano sound ... We can distinguish these sounds, mainly according to the sound ().

A. loudness b tone c frequency d timbre

13. In the following operations, it is () that can change the tone of the object sound.

A, pluck the strings hard; Paint some rosin on the bow hair of erhu.

C. pull the bow hard. Turn the knob of the violin.

14. Regarding the function of the amplifier, the following statement is true ().

A, change the tone b, change the loudness c, change the timbre d and change the frequency.

15. Figure 3 is a concave road design, which can control the impact of noise generated by car driving on the environment. Which of the following methods is adopted in this design to reduce noise ()?

A, weaken at the sound source; b, weaken during propagation.

C, weakening D in the human ear, the above options are incorrect.

16. Noise control is one of the main projects of urban environmental protection. Which of the following measures cannot reduce noise? ()

A. it is forbidden for motor vehicles to whistle in urban areas. Reduce the emission of carbon dioxide gas.

C. install a muffler on the automobile exhaust pipe. D plant a variety of grass and trees on both sides of urban streets and open spaces.

17. When insects fly, their wings vibrate. Butterflies flap their wings 5-6 times per second, and bees flap their wings 300-400 times per second. When they are flying behind you, you should listen to your hearing ().

A.i can feel butterflies flying behind you. I can feel bees flying behind you.

C.you can feel them flying behind you. D. you can't feel them flying behind you.

18. When classmate A speaks, the vocal cords vibrate 900 times in 3s, while when classmate B speaks, the vocal cords vibrate 1470 times in 5s, so compare the tones of these two students ().

A, A is higher, B is higher, B is higher, C is the same, D is incomparable.

19. In the following experiments and examples, it is .........................................................................................................................................................

A. Call the BP machine placed in vacuum with your mobile phone. The BP machine displays the mobile phone number, but you can't hear the call from the BP machine.

B. People see lightning first, and then they can hear thunder in the distance at regular intervals.

C sprinkle some foam crumbs on the surface of the drum. When you beat the drum, you can see that the foam crumbs keep jumping.

The astronauts who landed on the moon can only talk by radio even if they are very close.

Second, fill in the blanks:

1. In windy weather, the wires erected by the roadside buzz, which is caused by wires. Fish that can take the bait will be scared away by the sound or footsteps on the shore, indicating that they can transmit sound.

2. Put a lighted candle in front of the speaker. When there is a strong sound in the speaker, you can see the flame of the candle, which means that there are sound waves.

3. Compared with the buzz of mosquitoes, _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

4. 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.

5. The main difference between soprano and bass is _ _ _ _ _ _ _. A classmate talking loudly and whispering is mainly the _ _ _ _ difference of voice.

6. Play the same key with different dynamics, make different sounds, play different keys with the same dynamics, make different sounds, play different instruments with the same dynamics, and make different sounds.

7. The range of sound waves that the human ear can hear is usually between _ _ _ _ _ Hz and _ _ _ _ Hz. The frequency above the hearing limit is called _ _ _ _ _ _, and the frequency below the hearing limit is called _ _ _ _ _. Monitoring and controlling ocean waves can help to reduce its harm and can be used to predict earthquakes and typhoons.

8. When Xiaohua was repairing the table in the kitchen at home, the sound of knocking on objects kept coming out. In order to avoid being disturbed when Xiao Ming was studying next door, Xiaohua adopted three schemes: ① put a rag where he was knocked; (2) the room and kitchen doors and windows are locked; (3) Tell Xiao Ming to plug his ears with headphones for the time being. Among the above three schemes, the first scheme is to reduce the noise there; The second is the weakening in the middle; The third is to reduce the noise in the workplace.

9. In the picture, A and B are the waveforms of two kinds of sounds. From the chart, we can see that:

The picture is the waveform of music, and the picture is the waveform of noise.

Third, short answer questions:

1. Give two examples of life or natural phenomena to illustrate that the sounding object is vibrating:

Example1_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _;

Example 2 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

2. Bite the upper end of the pencil gently 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. Compare these two sounds. The difference is:

(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?

Fourth, experimental inquiry questions:

1. The following table shows the speed of sound (m/s) in some media.

Air (0℃)33 1 seawater (25℃) 153 1

Air (15℃)340 ice 3230

Air (25℃)346 Copper (Rod) 3750

Cork 500 marble 38 10

Kerosene (25℃) 1324 Aluminum (Rod) 5000

Water (normal temperature) 1500 iron (bar) 5200

Please draw two conclusions from the above data.

Conclusion 1:;

Conclusion 2:.

2. As shown in the figure, press one end of the plastic scale tightly on the desktop, and the other end extends out of the desktop. Move the scale to make it vibrate, and listen to the sound when the scale vibrates.

(1) During the experiment, press the weighing pan with your hands close to the table, otherwise you will hear the sound of _ _ _ _ _ _ _ _ and the sound of the weighing pan knocking on _ _ _ _ _ _ _ _.

(2) The experiment changes the vibration frequency of the scale by changing _ _ _ _ _ _ _ _ _ _.

(3) Do this experiment with a steel ruler. When the length, vibration amplitude and speed of the steel ruler sticking out of the desktop are the same as those of the plastic ruler, the main difference in hearing sound is _ _ _ _ _ _ _ _ _ (fill in loudness, tone or timbre).

3. In the process of learning to play the guitar, Xiaohua found that the pitch of the sound produced by the strings was influenced by many factors.

He decided to study it. After discussing with his classmates, he put forward the following conjecture:

Conjecture 1: The pitch of the sound produced by the strings may be related to the cross-sectional area of the strings.

Conjecture 2: The pitch of the sound produced by the strings may be related to the length of the strings.

Conjecture 3: The pitch of the sound produced by the strings may be related to the material of the strings.

In order to verify the correctness of the above conjecture, they found nine strings listed in the table below. Because the pitch depends on the vibration frequency of the sound source, they borrowed an instrument that can measure the vibration frequency to carry out the experiment.

Number material length (cm) Cross-sectional area (mm2)

A copper coin 600.76

Copper B 600.89

Copper 60 1.02

Copper 800.76

E copper

F copper 1000.76

G steel 80 1.02

H nylon 80 1.02

I nylon 100 1.02

(1) In order to verify the first conjecture, the string numbered,, should be selected for the experiment.

(2) In order to verify the second conjecture, the string numbered, should be selected for the experiment.

(3) Some material specifications in the table are not filled in. In order to test the third conjecture, we must know this item: please fill in the missing data in the form.

(4) With the progress of the experiment, Xiaohua thinks that the pitch of the strings may also be related to the tightness of the strings. In order to verify this conjecture, the necessary operations are:

Xiao Ming wants to compare the sound insulation performance of several materials (clothes, tinfoil paper and foam plastic). In addition to the materials to be tested, there are also available equipment: tuning fork, mechanical alarm clock and shoe box. In this experiment is suitable for the sound source is _ _ _ _ _;

Xiaoming put the sound source into the shoe box, which is full of materials to be tested. He conceived two experimental schemes, which you think are _ _ _ _ _ _ _.

A, let people stand at a certain distance from the shoe box and compare the loudness of the sound they hear.

B, let people listen to the sound, while retreating until they can't hear the sound, and compare the distance from here to the shoe box.

The phenomenon obtained through the experiment is shown in the table, and the order of sound insulation performance of the material to be tested from good to bad is _ _ _ _ _ _ _ _.

5. The speed of sound propagation is related to temperature. The following table shows the data of sound velocity changing with temperature.

Air temperature /℃-20- 100 102030

Sound speed/(m/s) 26538+083243335336

(1) Please give a vivid description of the relationship between sound speed and temperature in the coordinates shown in the figure.

(2) Please find out the sound speed when the temperature is 15℃ according to the image you made.

_ _ _ _ _ _ _ _ m/s