• 2022-05-27
    球体[tex=8.286x1.429]4FMDVPLuD57GDhXGjCa6CCjyX/GWL4gToCUW9lfeKZ3VYhgQsvR1QdT/H2fuyUjg[/tex]内,各点处的密度的大小等于该点到坐标原点的距离的平方。试求这球体的重心。
  • [b]解[/b]      由于此球体关于[tex=2.5x1.286]dbbkdsF3B0kxtqPKbabMKA==[/tex]平面的对称性, 显见 [tex=3.143x1.214]b7kNL/RZhby+B02TrX+mBZHyD7nMSTmWwd3Wp2UD/aY=[/tex];下求[tex=0.5x0.857]bIrzjwgFBYhTQIGgX0qQZA==[/tex] .[tex=0.786x1.0]GgtgXpJRsGaXCgpYisebFQ==[/tex]为球体,用球坐标计算三重积分。将球坐标待入球面方程,得[tex=7.286x1.214]kw4w9LRsEFvSKPu5/vxXmw7AyIAm5ZsKuf/znOgygLWczHKAuy8vCt0TVE5YLTw2[/tex]又显见[tex=4.714x1.143]bedwlP/ysas+R9v9jh7RrsF0aZFJPSqPXbj289+a0Sdz6NvQDebhUPetI1nIZMlg[/tex], [tex=6.429x1.357]CpuB0W6uzUVGuVPRGdxRb+TmhhvELP9wcX8YtTw0XZSLGIpxA0LYQQLMgAsIAk2+[/tex]质量[tex=1.786x1.0]SqRQZdSy3iTBjdcd2Yg8zw==[/tex][tex=16.357x2.857]Xron4GG90VAk3dDkQdPde8aaaSd62hJgSVFVXI2fNw3mT7yHbyC7CTwiWTaMm4bqhcM/8Av2+KQ7UYQYMS8JisvvMKMLkkNjwBzFf4+UOUne711pUu+XU3Fw3tR2YfdD9s7ZFL+GqfLhI6wUEWgsAVbZZjO1ctDFmq9KC45fn2dFU+eOXYM/2f6KbEq3gpx4[/tex]          [tex=13.5x2.857]w5a+RhbJ34V9w0lyNy3xj7/RXOS34YYIEufKlgRhihLQyEHUGpb8KA5AWlfDZjD6/jTKSC5KfDCQXyCIOAZwzwQUhwH+mqzxQ9ACln8EQrXPM/u7sr0ySQdi5D2D4ezl[/tex]          [tex=10.071x2.643]sjUlSMXbQQcZA3BhJo9veg5HvjapmvpItDrrR+yLz0Rm8w56RViIl0s8KIzxnD3v7vMRPn6pGe3hDu0I8l9as2RmHKaAdE2nnZjYV++lfKAca4SXVGHXFbXWtmYaPyTzc/pA5YMVEj/of8kuFY4DFw==[/tex]          [tex=4.143x2.357]wGtqfH7PBjPqUOHqx5CAO34RdesiMRFgyuX7eej9Qog=[/tex]静矩  [tex=8.286x3.357]iB/yIJHKnnIuy5SFL0cXTpRJOCpIPTNBLp5RhNxp9SBQlR8ZrfzfzFBJT4QJtrtY[/tex][tex=19.643x2.857]Xron4GG90VAk3dDkQdPde8aaaSd62hJgSVFVXI2fNw3mT7yHbyC7CTwiWTaMm4bqhcM/8Av2+KQ7UYQYMS8JisvvMKMLkkNjwBzFf4+UOUne711pUu+XU3Fw3tR2YfdDMq6TmsVHOcL6MM+yByZCT87UuwnmUDz3ozWNeUXSBJw1Gay4R6pefwfpXP4+f9hbRJfJxmhoLYur6cQp5uj5gg==[/tex]              [tex=15.857x2.857]w5a+RhbJ34V9w0lyNy3xj7/RXOS34YYIEufKlgRhihLCW5aAG1NpJBo+Ex2zDiJYFnRH8whtPTneCGQIiUGSE9WO/bRpyAwJX67Kjj2/0rZTar60aSe/oESgBDX6lBRhT0EbBIdC+CdbrUiOEmEKYg==[/tex]              [tex=10.071x2.643]sjUlSMXbQQcZA3BhJo9veg5HvjapmvpItDrrR+yLz0Rm8w56RViIl0s8KIzxnD3v7vMRPn6pGe3hDu0I8l9as2RmHKaAdE2nnZjYV++lfKAca4SXVGHXFbXWtmYaPyTzc/pA5YMVEj/of8kuFY4DFw==[/tex]              [tex=4.143x2.357]wGtqfH7PBjPqUOHqx5CAO34RdesiMRFgyuX7eej9Qog=[/tex]静矩[tex=8.286x3.357]iB/yIJHKnnIuy5SFL0cXTpRJOCpIPTNBLp5RhNxp9SBQlR8ZrfzfzFBJT4QJtrtY[/tex][tex=19.5x2.857]Xron4GG90VAk3dDkQdPde8aaaSd62hJgSVFVXI2fNw3mT7yHbyC7CTwiWTaMm4bqhcM/8Av2+KQ7UYQYMS8JisvvMKMLkkNjwBzFf4+UOUnkHCxU8X9MGYILCMnq1XNKKT/uWKZ+8vs+G0lqe015pfGpvIVCYUQEPguq7SQF3xAtZJ1IZyTD1zLODQHi1QEU[/tex]           [tex=15.857x2.857]w5a+RhbJ34V9w0lyNy3xj7/RXOS34YYIEufKlgRhihLCW5aAG1NpJBo+Ex2zDiJYFnRH8whtPTneCGQIiUGSE9WO/bRpyAwJX67Kjj2/0rZTar60aSe/oESgBDX6lBRhT0EbBIdC+CdbrUiOEmEKYg==[/tex]           [tex=10.786x2.643]nRXEba7S0DahQ/sgfe2M3SVLHWzFOm7LFh54+8PbuEsinNuEL6BL1TQCSrIVV2rBi5uigEPfefuqnbPdVCE14Mmh/zIvXYiqwW0/41vfsw1HHsSw/mKmv7iRRKM6PlCPKozBA8LUCHZTDoFoPqdZyw==[/tex]           [tex=3.643x2.357]RjlBmPriNIZ6nMZLqR+OKAtQ1ynRwuyD6bV2NF3wVAw=[/tex][tex=8.143x2.429]JqD/C6Zu721wGmbikc2iYFrYpsyLvemhWUDHrI73izEsskgF7BwSkWCRo8DqLEVbA0sairrMuWigLiwk5zOhKw==[/tex]故该球体的重心在[tex=5.0x2.786]KAE/eB15Z6qVCSVTXpoe9ulyp5IqDIPd+iV5vpyWPCs=[/tex]处。

    内容

    • 0

      设球体 [tex=6.214x1.429]JfMnpkdfUBckNje06oWbk1gN/P52EuGpvOoUEC9d5VTdTc5ssVRONK0XgYt4GZXh[/tex] 上各点的密度等于该点到坐标原点的距离,求这球体的质量。

    • 1

      设球体 [tex=3.929x1.286]OgRXGBnuYUkrpNulxRW68D36NV9X5hevhTpuCfbJIg4=[/tex][tex=3.286x1.286]8UBoqWgIU0LEZK9ye4gOwmYF7i4S+RlL7M++VMzjL0E=[/tex] 上各点的密度等于该点到坐标原点的距离,求这个球体的质量.

    • 2

      球心在原点, 半径为 [tex=0.786x1.0]as0RCzgUx1oS48cKHRAVVg==[/tex] 的球体上的任意一点的密度与该点到球心的距离成正比.(1) 求这个球体的质量;(2) 求该球体对点 [tex=4.857x1.286]atOeeAzxRfNUHNvL2nODMZ51X7ib7tz0O0Xz5iE8Dd0=[/tex] 的转动惯量, 这里正常数 [tex=3.0x1.286]T5OFUM3yNZ9FVWgcs9BGYA==[/tex].

    • 3

      设球体[img=149x26]1802e977c538e3a.png[/img]内每一点[img=56x25]1802e977cd3ad1e.png[/img]处密度的大小等于该点到坐标原点距离的平方,则该球体的质心坐标为( )。 未知类型:{'options': ['', '', '', ''], 'type': 102}

    • 4

      设球体[img=149x26]1802e97ad2a8757.png[/img]内每一点[img=56x25]1802e97adaab9c3.png[/img]处密度的大小等于该点到坐标原点距离的平方,则该球体的质心坐标为( )。 未知类型:{'options': ['', '', '', ''], 'type': 102}