题目内容
两手对拉一弹簧秤,它的示数是10 N,这两手的拉力分别为( )
A.5 N,5 N B.10 N,10 N
C.0 N,0 N D.20 N,20 N
B
A.5 N,5 N B.10 N,10 N C.0 N,0 N D.20 N,20 N