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二力平衡的概念

> 有一架直升飞机重150000N，停在空中时，螺旋桨产生向上的举力，这个力的大小为______N；当它沿竖直方向匀速下降时，举力______（选填“变大”、“不变”或“变小”）．

问题：

发布时间：2024-09-11

有一架直升飞机重150000N，停在空中时，螺旋桨产生向上的举力，这个力的大小为N；当它沿竖直方向匀速下降时，举力（选填“变大”、“不变”或“变小”）．

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