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问题 选择题

把重为5N，体积为600cm3的物体投入水中，若不计水的阻力，当物体静止时，下列说法正确的是（g取10N／kg）（　　 ）

A．物体漂浮F浮＝6N

B．物体悬浮F浮＝5N

C．物体漂浮F浮＝5N

D．物体沉在水底F浮＝5N

答案

答案：C

题目分析：假设物体完全浸没于水中，

此时物体所受浮力为：，

因为，所以该物体静止时将浮在水面上，因此物体静止时所受的浮力为；

本题答案选C

完形填空

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