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<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">如图所示为一种自制简易密度计，它是在木棒的一端缠绕一些铜丝做成的，用它来测量液体密度时，该密度计<u>　  　</u>在被测液体中（选填“悬浮”、“漂浮”或“下沉”）。将其分别放入装有液体密度为ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">1</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">和ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">的两个烧杯中，可以判断：ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">1</span></span></span></sub><u><span style="line-height:150%"><span style="font-family:宋体">　 　</span></span></u><span style="line-height:150%"><span style="font-family:宋体">ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">．若该密度计两次测量中排开液体的质量分别为m</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">1</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">、m</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">，则m</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">1</span></span></span></sub><u><span style="line-height:150%"><span style="font-family:宋体">　 　</span></span></u><span style="line-height:150%"><span style="font-family:宋体">m</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">．（后两空选“＜”、“＝”或“＞”）</span></span></span></span></span><br />
<img src="/uploads/meth/20210417/55b63a588f4c2db4b48fe6516d73c0db.png" style="float: right; width: 210px; height: 147px;" />

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<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">解：密度计放在两种液体中都漂浮，根据漂浮条件可知，密度计在甲、乙两种液体中受到的浮力都等于密度计受到的重力G，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">即：F</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">浮1</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">＝F</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">浮2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">＝G，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">由图知密度计排开液体的体积V</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">排1</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">＞V</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">排2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">由阿基米德原理F</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">浮</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">＝ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">液</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">V</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">排</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">g可知，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">密度计排开甲液体的体积大，所以甲液体的密度小，即ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">1</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">＜ρ</span></span><sub><span style="font-size:12.0pt"><span style="line-height:150%"><span style="font-family:宋体">2</span></span></span></sub><span style="line-height:150%"><span style="font-family:宋体">。</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">两次浮力相等，根据阿基米德原理可知两次排开液体的重力相等，所以两次排开液体的质量相等。</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">故答案为：漂浮；＜；＝。</span></span></span></span></span>

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