釣魚島(The Diaoyu Islands)自古就是我國固有領(lǐng)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385 km、基隆市約190 km。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480 km。則下列說法中不正確的是

A.該海監(jiān)船位移是480 km,路程356km
B.該海監(jiān)船位移是356 km,路程480 km
C.該海監(jiān)船在海上航行時,確定其位置時可以將該海監(jiān)船看成質(zhì)點
D.若知道此次航行時間可求出此次航行的近似平均速度

A

解析試題分析:位移表示由初位置指向末位置的有向線段,路程表示實際運動軌跡的長度,故路程大于等于位移大小,所以該海監(jiān)船位移是356 km,路程480 km,A錯誤,B正確,
該海監(jiān)船在海上航行時,確定其位置時其大小和形狀可以忽略故能看做質(zhì)點,C正確,
平均速度等于位移與時間的比值,故給出時間即可求出平均速度,D正確,
故選A
考點:考查了位移,路程,質(zhì)點,平均速度等概念
點評:平均速度等于位移與時間的比值,平均速率等于路程與時間的比值,路程大于等于位移大小,當(dāng)做單向直線運動時,位移大小等于路程

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