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> 关于运动和力的描述，下列说法正确的是 A.静止放在水平桌面上的书受到的支持力和重力是一对平衡力 B.划船时，船桨对水有推力，但水对船桨没有作用力 C.物体受到力的作用，其运动状态就会改变 D.行驶中的汽车突然刹车时，车上乘客身体上部前倾是由于受到座位靠背的推力

问题：

发布时间：2020-03-13

关于运动和力的描述，下列说法正确的是

A.静止放在水平桌面上的书受到的支持力和重力是一对平衡力
B.划船时，船桨对水有推力，但水对船桨没有作用力
C.物体受到力的作用，其运动状态就会改变
D.行驶中的汽车突然刹车时，车上乘客身体上部前倾是由于受到座位靠背的推力

参考答案：

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