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                </infopoint><Keyword>声现象,总结,练习</Keyword><CopyFrom>原创</CopyFrom><SoftType></SoftType><CopyrightType></CopyrightType><DecompressPassword></DecompressPassword><OperatingSystem></OperatingSystem><UpdateTime>2006年09月19日</UpdateTime><RegUrl></RegUrl><DemoUrl /><DefaultPicUrl>/UploadFiles/nopic.gif
     </DefaultPicUrl><Intro>
				声现象知识点总结
				　 　 
		
		
				
						1
						．声音是由于物体
						产生的，声</Intro><SoftIntro2>
				声现象知识点总结
				　 　 
		
		
				
						1
						．声音是由于物体
						产生的，声音产生的条件，一是要有发声体，二是发声体要
						，振动的物体叫做
						。
				
		
		
				
						注意：（
						1
						）发声体既可以是固体
						,
						如发出鼓声的鼓面
						;
						也可以是
						，如
						；还可以是
						，如
						。（
						2
						）发声体肯定在
						，但振动却不一定发出可听声。
				
		
		
				
						2
						．声音靠
						传播，（可以是固体、液体或者气体），声音以
						的形式传播，称为声波，声波具有能量，如：
						。声音在
						中不能</SoftIntro2><SoftIntro>
    【内容简介】
				声现象知识点总结
				　 　 
		
		
				
						1
						．声音是由于物体
						产生的，声音产生的条件，一是要有发声体，二是发声体要
						，振动的物体叫做
						。
				
		
		
				
						注意：（
						1
						）发声体既可以是固体
						,
						如发出鼓声的鼓面
						;
						也可以是
						，如
						；还可以是
						，如
						。（
						2
						）发声体肯定在
						，但振动却不一定发出可听声。
				
		
		
				
						2
						．声音靠
						传播，（可以是固体、液体或者气体），声音以
						的形式传播，称为声波，声波具有能量，如：
						。声音在
						中不能传播，在不同介质中传播的速度
						（相同
						/
						不同），它们从大到小依次应该是：
						
								　 　 
						
				
		
		
				
						。声音在空气（
						15
						℃）中的传播速度为
						m/s
						。
				
		
		
				
						3
						．声音的三要素是
						、
						、
						。
				
		
		
				
						4
						．
						叫做响度，响度跟发声体的
						和
						有关。
						越大，响度越大；
						越小，响度越小；离发声体越远，听到的声音越
						。另外，如果使声音集中向一个方向传播，我们也能听到较大响度的声音，例如：
						。
				
		
		
				
						分贝是
						的单位，它用符号
						来表示，平时我们可以在
						上面看到它。当汽车经过噪声监测装置时，它的示数将
						（变大
						/
						变小）。
				
		
		
				
						5
						<span style="font-family: 宋体; mso-ascii-font-family: 'Times N</SoftIntro><SoftIntroEncode>
				声现象知识点总结
				　 　 
		
		
				
						1
						．声音是由于物体
						产生的，声音产生的条件，一是要有发声体，二是发声体要
						</SoftIntroEncode><special /><DownloadUrl></DownloadUrl><Content>&lt;p align="center" class="MsoNormal" style="text-align: center; margin: 0cm 0cm 0pt"&gt;
				&lt;span style="font-family: 黑体; font-size: 16pt; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: 'Times New Roman'"&gt;声现象知识点总结&lt;/span&gt;
				&lt;span lang="EN-US" style="font-size: 16pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 黑体"&gt;　 　 &lt;/span&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;1&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音是由于物体&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;产生的，声音产生的条件，一是要有发声体，二是发声体要&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，振动的物体叫做&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;注意：（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;1&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;）发声体既可以是固体&lt;/span&gt;
						&lt;span lang="EN-US"&gt;,&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;如发出鼓声的鼓面&lt;/span&gt;
						&lt;span lang="EN-US"&gt;;&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;也可以是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，如&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;；还可以是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，如&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;2&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;）发声体肯定在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，但振动却不一定发出可听声。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;2&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音靠&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;传播，（可以是固体、液体或者气体），声音以&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;的形式传播，称为声波，声波具有能量，如：&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。声音在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;中不能传播，在不同介质中传播的速度&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;（相同&lt;/span&gt;
						&lt;span lang="EN-US"&gt;/&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;不同），它们从大到小依次应该是：&lt;/span&gt;
						&lt;u&gt;
								&lt;span lang="EN-US"&gt;　 　 &lt;/span&gt;
						&lt;/u&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。声音在空气（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;15&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;℃）中的传播速度为&lt;/span&gt;
						&lt;span lang="EN-US"&gt;m/s&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;3&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音的三要素是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;、&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;、&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;4&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;叫做响度，响度跟发声体的&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;和&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;有关。&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;越大，响度越大；&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;越小，响度越小；离发声体越远，听到的声音越&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。另外，如果使声音集中向一个方向传播，我们也能听到较大响度的声音，例如：&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;分贝是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;的单位，它用符号&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;来表示，平时我们可以在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;上面看到它。当汽车经过噪声监测装置时，它的示数将&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;（变大&lt;/span&gt;
						&lt;span lang="EN-US"&gt;/&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;变小）。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;5&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times N</Content><banben>苏科版</banben><area>不限</area><type>试题试卷</type><type2>专供vip会员</type2><ico>doc</ico><video>&lt;p align="center" class="MsoNormal" style="text-align: center; margin: 0cm 0cm 0pt"&gt;
				&lt;span style="font-family: 黑体; font-size: 16pt; mso-bidi-font-size: 12.0pt; mso-ascii-font-family: 'Times New Roman'"&gt;声现象知识点总结&lt;/span&gt;
				&lt;span lang="EN-US" style="font-size: 16pt; mso-bidi-font-size: 12.0pt; mso-fareast-font-family: 黑体"&gt;　 　 &lt;/span&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;1&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音是由于物体&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;产生的，声音产生的条件，一是要有发声体，二是发声体要&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，振动的物体叫做&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;注意：（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;1&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;）发声体既可以是固体&lt;/span&gt;
						&lt;span lang="EN-US"&gt;,&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;如发出鼓声的鼓面&lt;/span&gt;
						&lt;span lang="EN-US"&gt;;&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;也可以是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，如&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;；还可以是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，如&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;2&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;）发声体肯定在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;，但振动却不一定发出可听声。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;2&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音靠&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;传播，（可以是固体、液体或者气体），声音以&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;的形式传播，称为声波，声波具有能量，如：&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。声音在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;中不能传播，在不同介质中传播的速度&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;（相同&lt;/span&gt;
						&lt;span lang="EN-US"&gt;/&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;不同），它们从大到小依次应该是：&lt;/span&gt;
						&lt;u&gt;
								&lt;span lang="EN-US"&gt;　 　 &lt;/span&gt;
						&lt;/u&gt;
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		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
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						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。声音在空气（&lt;/span&gt;
						&lt;span lang="EN-US"&gt;15&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;℃）中的传播速度为&lt;/span&gt;
						&lt;span lang="EN-US"&gt;m/s&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
				&lt;/font&gt;
		&lt;/p&gt;
		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;3&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．声音的三要素是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;、&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;、&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
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				&lt;font size="3"&gt;
						&lt;span lang="EN-US"&gt;4&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;．&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;叫做响度，响度跟发声体的&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;和&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;有关。&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;越大，响度越大；&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;越小，响度越小；离发声体越远，听到的声音越&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。另外，如果使声音集中向一个方向传播，我们也能听到较大响度的声音，例如：&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;。&lt;/span&gt;
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						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;分贝是&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;的单位，它用符号&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;来表示，平时我们可以在&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;上面看到它。当汽车经过噪声监测装置时，它的示数将&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;（变大&lt;/span&gt;
						&lt;span lang="EN-US"&gt;/&lt;/span&gt;
						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"&gt;变小）。&lt;/span&gt;
				&lt;/font&gt;
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		&lt;p align="left" class="MsoNormal" style="margin: 0cm 0cm 0pt"&gt;
				&lt;font size="3"&gt;
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						&lt;span style="font-family: 宋体; mso-ascii-font-family: 'Times N</video><DefaultPicUrl>
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<div id="bjtidu_ground" onclick="closeModel()"> </div>
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