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In the process of sound transmission, the following statement is correct () A. The timbre will gradually change B. The tone will gradually decrease C. The loudness will gradually decrease D. The timbre, pitch and loudness of the sound will not change
A. In the process of sound transmission, the timbre is determined by the sounder itself, so it will not change; So a is wrong;
B. In the process of sound transmission, the tone will not change; So B error;
C. In the process of sound propagation, the loudness decreases because it is farther and farther away from the sounder; Therefore, C is correct;
D. In the process of sound propagation, the timbre and tone of sound will not change, but the loudness will decrease; Therefore, D error;
Therefore, C
A physics multiple choice question about sound propagation Regarding the propagation of sound, the following error is () A. Sound may be transmitted by gas, liquid or solid, or by radio waves B. When hearing the roar of shells or bullets on the battlefield, lie down immediately to avoid the shells or bullets Please say the reason
Choose B
Because the speed of light is faster than the speed of sound, it fell down when you heard the sound of shells. It's already late and it's already blown up, so choose B
The speed of sound in the air is 20400 () per minute Options include: 1. Kilometer 2, meter 3, decimeter
At fifteen degrees Celsius, the speed of sound propagation in the air is 340m / s
340m/s*60=20400m/min
So it's 2
At the opening ceremony of the Beijing Olympic Games, the powerful "beating fou and singing" was wonderful. The fou sound was due to the fou surface______ The spectacular scene was passed by synchronous communication satellites______ Waves travel all over the country
The fou sound is generated by the vibration of the fou surface, and then transmitted to the audience's ears through the air. This spectacular scene is transmitted to all parts of the world by synchronous communication satellites through electromagnetic waves
So the answer is: vibration, electromagnetic
When the sound source vibrates in the air, it will cause the surrounding air—— Completion
It vibrates and continuously propagates outward to form waves
Sound propagates the () of the sound source through the medium in the form of (), which is sound wave
Sound propagates the (vibration) of the sound source through the medium in the form of (wave). This is sound wave
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