如图所示,在弹簧测力计的两侧沿水平方向各加4N拉力并使其保持静

如图所示,在弹簧测力计的两侧沿水平方向各加4N拉力并使其保持静止,此时弹簧测力计的示数为(   )

A.0N             B.2N            C.4N              D.8N

           

 

答案

C

解析:略

 

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