耳朵贴在长铁管道一端，敲击管的另一端，为什么会听见两次敲击声？
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绛旓細鎵浠ュ惉鍒颁袱娆:绗竴娆℃槸閾佷紶鏉ョ殑,绗簩娆℃槸姘翠紶鏉ョ殑.(2)濡傛灉鏄按绠,浼氬惉鍒颁笁娆 鍥犱负澹伴煶鍦ㄦ按涓殑閫熷害鏄1450m/s,澹伴煶鍦閾佺涓熷害涓5000m/s,鑰屽０闊冲湪绌烘皵涓殑閫熷害涓340m/s.鎵浠ュ惉鍒颁笁娆:绗竴娆℃槸閾佷紶鏉ョ殑,绗簩娆℃槸姘翠紶鏉ョ殑,绗笁娆℃槸绌烘皵浼犳潵鐨.娉:鍙湁鏃堕棿鐩稿樊姣0.1绉掗暱鏃朵汉鎵嶈兘鍒嗚鲸鍑烘潵...
绛旓細浜虹殑鍚姏鍒嗚鲸鍔涘ぇ绾﹀湪0.1绉掑乏鍙炽傚０闊充細娌块挗绠″拰绌烘皵涓や釜閫斿緞浼犳挱銆傞氳繃閽㈢浼犲埌鑰涓殑澹伴煶姣旂┖姘斾紶杩囨潵鐨勬椂闂存棭0.1绉掍互涓婏紝鎵嶈兘鍚埌涓ゆ鍝嶅０銆傚０闊冲湪閽㈢浼犳挱閫熷害澶ф5000m/s锛屽０闊冲湪绌烘皵浼犳挱閫熷害澶ф340m/s銆傚綋涓や釜閫斿緞浼犳挱鐨勫０闊冲樊0.1绉掑埌锛岃閽绠￠暱x鏃讹細x/340-x/5000=0.1 x=36.4m 閽㈢闀...
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绛旓細鎯宠鍚埌涓ゅ０,閭ｄ箞鍙煡涓澹版潵鑷抽搧鐨勪紶鎾;鍙︿竴澹版潵鑷崇┖姘旂殑浼犳挱,鍙堢煡浜鑰鐨勫弽鏄犳椂闂村ぇ浜庣瓑浜0.1绉.璁捐嚦灏戣x绫,鍒欐牴鎹鎰,寰 X/340-X/5000鈮0.1 瑙ｅ緱: X鈮31.83鍚32 绛:鑷冲皯闇瑕 32绫崇殑閾佺.
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