问题
填空题
噪声的发声体做______振动时发出的声音．如图所示，甲和乙是两种声音的波形图，其中______图是噪声的波形．
答案
从物理学角度看，噪声是指发声体做无规则振动时发出的声音，对比甲与乙，不难看出：甲波形很有规律，属于乐音；乙杂乱无章属于噪声．
故答案为：无规则；乙．
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噪声的发声体做______振动时发出的声音．如图所示，甲和乙是两种声音的波形图，其中______图是噪声的波形．
从物理学角度看，噪声是指发声体做无规则振动时发出的声音，对比甲与乙，不难看出：甲波形很有规律，属于乐音；乙杂乱无章属于噪声．
故答案为：无规则；乙．
| Choose the best response from A to F in the box according to the sentence given. Each choice should be used only once. | |
| ( )1. Do you mind if I smoke here? ( )2. I'm going to take an exam. ( )3. Dad, there's something wrong with your computer. ( )4. Could you lend me some books? ( )5. What about having a bottle of orange juice?
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