一跳伞运动员和伞的总质量为70kg，张开伞一段时间后以5m/s的速度竖

一跳伞运动员和伞的总质量为70kg，张开伞一段时间后以5m/s的速度竖直匀速下降，这时运动员（包括伞）受到的阻力为 N。

答案

700 N解析:
略

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