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Suppose the sound propagation speed in the air is 340m / s and in the steel is 1500m / s. one person hits one end of the iron bridge with a hammer and the other person hears two sounds at the other end with a difference of 0.5 seconds. What is the length of the iron bridge? If there is an obstacle at one end of the bridge, how many echoes can the hammerer hear?
(1500-340)*0.5=580m
If there is an obstacle at one end of the bridge, the hammerer can hear two echoes
How many meters per second does sound travel through the air?
The speed of sound in uniform air is 340 meters per second
The propagation speed of sound in the air is 340 and in iron is 4900, The propagation speed of sound in the air is 340m / s and 4900m / s in iron. Today, a person knocks at one end of an iron pipe, and people at the other end can hear two knocks, If the two knocking sounds are separated by 0.6 seconds, what is the length of the iron pipe?
Set the length of iron pipe as m;
Then: M / 340-m / 4900 = 0.6
(4900m-340m)/340*4900=0.6
m(4900-340)=0.6*340*4900
m=0.6*340*4900/(4900-340)
=0.6*340*4900/4560
≈219m
Why is the sound of railway tracks low? In the past, when the train was moving, there was always a click, click sound, but now it doesn't. is it unnecessary to consider thermal expansion, or the use of new materials will not expand, or the gaps left in the past are useless?
In the past, the railway line was a jointed line, that is, the line was spliced by 25m steel rails, and there would be a click sound when the train passed through the joint. Now the main line of the railway is basically a seamless line. The factors of thermal expansion and cold contraction are considered for both the jointed line and the seamless line. In the past, the jointed line used the method of reserving rail joints to make the steel rails not
After hitting one end of a long rail, two sounds are heard at the other end, with an interval of 2S. Find the length of the long rail The sound propagation speed in the rail is 5200m / s and 340m / s in the air
Set the distance of this rail as X
There is a theory that the first heard sound is transmitted through the railway track, and the following equation is obtained
x/5200-x/340=2
Calculated x = 727.6 (approximately equal to)
A: the length of this long rail is about 727.6m
After one end of the long rail is hit, the sound is heard twice in another section at an interval of 2 seconds. Find the length of the rail (the sound travels at a speed of 340m in the air),
By querying the average propagation speed of sound wave in the rail V1 = 5km / s, the propagation speed of sound in the air V2 = 340m / s, and the rail length L = 340x (T + 2) = 5000xt, t = 0.1459s, that is, the propagation time of sound wave in the rail, from which the rail length L = 729.5m can be obtained
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