如图所示，a、b两个质量相同的球用线连接，a球用线挂在天花板上，

如图所示，a、b两个质量相同的球用线连接，a球用线挂在天花板上，b球放在光滑斜面上，系统保持静止，以下图示哪个是正确的(　　)

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解析:

略

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如图所示，a、b两个质量相同的球用线连接，a球用线挂在天花板上，

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