釣魚島（The Diaoyu Islands）自古就是我國固有領土，又稱釣魚臺、釣魚臺群島、釣魚臺列島，位置在距溫州市約356km、福州市約385km、基隆市約190km．若我國某海監(jiān)船為維護我國對釣魚島主權(quán)，從溫州出發(fā)去釣魚島巡航，到達釣魚島時航行了480km．則下列說法中不正確的是（　�。�
分析：位移是矢量，有大小，有方向，可以用由初始位置指向末位置的有向線段表示；路程表示運動軌跡的長度，在單向直線運動中，位移的大小等于路程．
能否看作質(zhì)點物體本身無關，要看所研究問題的性質(zhì)，看物體的形狀和大小在所研究的問題中是否可以忽略．平均速度等于總位移除以總時間．
解答：解：A、位移是矢初始位置指向末位置的有向線段的長度，所以位移為356 km，路程表示運動軌跡的長度，所以路程為480 km，故A錯誤，B正確；
C、該海監(jiān)船在海上航行時，其大小和形狀對其位置沒有影響，所以可以看成質(zhì)點，故C正確；
D、平均速度等于總位移除以總時間，知道位移和時間即可求解平均速度，故D正確．
本題選錯誤的
故選A
點評：解決本題的關鍵理解路程和位移的區(qū)別及聯(lián)系：位移是矢量，有大小，也有方向，可以用由初始位置指向末位置的有向線段表示；路程表示運動軌跡的長度，只有大小，沒有方向．在單向直線運動中，位移的大小等于路程．
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