If the helicopter is going to hover in place, the force it pushes on these tiny air balls will have to be equal to the weight of the helicopter.

如果想使直升机悬停于某处，这些空气微粒的推力必须相当于直升机重量。

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The precise critical force of a system can be deduced from the fact that the determinant of stiffness matrix of the system is equal to zero in the critical condition.

由结构刚度矩阵行列式值为零的失稳条件导出结构失稳特征方程，从而精确地确定系统临界力值。

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If Lisbon comes into force, the parliament will be the equal of the council in almost all EU legislation, gaining new rights over, for example, farm subsidies, fisheries, asylum and immigration.

ECONOMIST: The EU after the Irish vote