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> 一个物体静止在光滑水平面上，先对物体施一水平向右的恒力 F 1，经 t s后撤去 F 1，立即再对它施一水平向左的恒力 F 2经 t s后物体回到出发点，在这一过程中， F 1、 F 2分别对物体做的功之比为 W 1∶ W 2=________．

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发布时间：2024-09-11

一个物体静止在光滑水平面上，先对物体施一水平向右的恒力 F ₁，经 t s后撤去 F ₁，立即再对它施一水平向左的恒力 F ₂经 t s后物体回到出发点，在这一过程中， F ₁、 F ₂分别对物体做的功之比为 W ₁∶ W ₂=________．

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