挑战习题
1/5单选题
难度:

1.

有四个实验现象:不能够说明声音产生的条件的实验(  )


A

将正在发声的音叉接触水面,水面溅起水花

B

吹响笛子,手指按住不同的孔,发出不同的声音

C

吊着的大钟上固定一支细小的笔,钟敲响后,用纸在笔尖上迅速水平拖过,纸上出现弯曲的图象

D

锣发声的时候,用手按住锣面,锣声消失

提示1:
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正确答案:Qg==
PHA+QeOAgeWPkeWjsOeahOmfs+WPieS8muaMr+WKqO+8jOaJgOS7peW9k+aOpeinpuawtOmdouaXtuS8mua6hei1t+awtOiKse+8jOiDveWkn+ivtOaYjuWjsOmfs+S6p+eUn+eahOadoeS7tuaYr+eJqeS9k+aMr+WKqO+8jOS4jeespuWQiOmimOaEj++8mzxicj5C44CB5ZC556yb5a2Q5pe25piv6Z2g56m65rCU5p+x55qE5oyv5Yqo5Y+R5Ye65aOw6Z+z77yM5b2T5oyJ5L2P5LiN5ZCM55qE5a2U5pe256m65rCU5p+x6ZW/5bqm5LiN5ZCM77yM6L+Z5qC356m65rCU5p+x55qE5oyv5Yqo5b+r5oWi5LiN5ZCM77yM5omA5Lul5Y+R5Ye65aOw6Z+z55qE6Z+z6LCD5LiN5ZCM77yM5LiN6IO95aSf6K+05piO5aOw6Z+z55qE5Lqn55Sf5p2h5Lu277yM56ym5ZCI6aKY5oSP77ybPGJyPkPjgIHlpKfpkp/ooqvmlbLlk43lkI7kvJrmjK/liqjvvIzmiYDku6XkvJrluKbliqjpk4XnrJTmjK/liqjvvIzmiYDku6XlvZPnurjlnKjnrJTlsJbkuIrov4XpgJ/msLTlubPmi5bov4fvvIznurjkuIrlh7rnjrDlvK/mm7LnmoTlm77osaHvvIzog73lpJ/or7TmmI7lo7Dpn7PkuqfnlJ/nmoTmnaHku7bmmK/niankvZPmjK/liqjvvIzkuI3nrKblkIjpopjmhI/vvJs8YnI+ROOAgeW9k+eUqOaJi+aMieS9j+aMr+WKqOeahOmUo+mdouaXtu+8jOmUo+mdouaMr+WKqOWBnOatou+8jOWPkeWjsOWBnOatou+8jOiDveWkn+ivtOaYjuWjsOmfs+S6p+eUn+eahOadoeS7tuaYr+eJqeS9k+aMr+WKqO+8jOS4jeespuWQiOmimOaEj++8mzxicj7mlYXpgIlC77yOPC9wPg==