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发表于 2019-9-13 23:46:11 | 显示全部楼层 |阅读模式
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?2014??????R?????????O?????????A??????????O???????????????????v????????OA?????v??????????????????????????A???????g ????????

O???h ?_________??????????? ?_________?

?2008?????????????????????M????r1????N????r2???????????????????n?????????????????????????BC? A?????????? B?????????? C???????? r1 n/ r2 D????????r2n/ r1

?2009???????????????a?b?c

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A?a?b?c?????????? B?a?b?c???????? C?a?b?????c?? D?c?????a?b??

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?????????????????( 1.46 )

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?2009????????????????????????????????????????????????????????????????????????????????????????????t??????????N????????????? = ____??????????????????????r1????????????_________????????????????????????????????v

=_______???????????

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A. B. C. D.

?2005???????????????????????????????( C ) A.?????????? B.?????????? C.?????? D.?????? ???

?2005??????????????????P?????????????????????m?????????????????R????????????????????????????????

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2

?????????g=10m/s ?? ?1??????????????V0? ?2?????????????????? 1m/s 0.2

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