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> 如图所示，木块在光滑水平面上，子弹A、B从木块两侧同时射入木块，最终都停在木块中，这一过程中木块向右运动，最后静止在水平面上，设子弹A、B的初动量大小分别为p A、p B，相对木块运动时，受到木块的恒定阻力，大小分别为f A、f B，由此可判断（　　） A．pA=pB B．pA＞pB C．fA＞fB D．fA＜fB

问题：

发布时间：2024-09-10

如图所示，木块在光滑水平面上，子弹A、B从木块两侧同时射入木块，最终都停在木块中，这一过程中木块向右运动，最后静止在水平面上，设子弹A、B的初动量大小分别为p _A、p _B，相对木块运动时，受到木块的恒定阻力，大小分别为f _A、f _B，由此可判断（　　）

A．p_A=p_B B．p_A＞p_B C．f_A＞f_B D．f_A＜f_B

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