釣魚(yú)島(The Diaoyu Islands)自古就是我國(guó)固有領(lǐng)土，又稱釣魚(yú)臺(tái)、釣魚(yú)臺(tái)群島、釣魚(yú)臺(tái)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(guó)某海監(jiān)船為維護(hù)我國(guó)對(duì)釣魚(yú)島主權(quán)，從溫州出發(fā)去釣魚(yú)島巡航，到達(dá)釣魚(yú)島時(shí)航行了480 km。則下列說(shuō)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(shí)，確定其位置時(shí)可以將該海監(jiān)船看成質(zhì)點(diǎn)
D．若知道此次航行時(shí)間可求出此次航行的近似平均速度
A

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(shí)際運(yùn)動(dòng)軌跡的長(zhǎng)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(cuò)誤，B正確，
該海監(jiān)船在海上航行時(shí)，確定其位置時(shí)其大小和形狀可以忽略故能看做質(zhì)點(diǎn)，C正確，
平均速度等于位移與時(shí)間的比值，故給出時(shí)間即可求出平均速度，D正確，
故選A
點(diǎn)評(píng)：平均速度等于位移與時(shí)間的比值，平均速率等于路程與時(shí)間的比值，路程大于等于位移大小，當(dāng)做單向直線運(yùn)動(dòng)時(shí)，位移大小等于路程
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