如图所示,质量为M的小车放在光滑水平面上,小车上用细线悬挂一

如图所示,质量为M的小车放在光滑水平面上,小车上用细线悬挂一质量为m的小球,Mm,用一力F水平向右拉小球(图甲),使小球和车一起以加速度向右运动,细线与竖直方向成θ角,细线的拉力为T,若用一力水平向左拉小车(图乙),使小球和车一起以加速度向左运动时,细线与竖直方向也成θ角,细线的拉力为T',则( 

       AT=T             BT>T           

       C=             D>

答案

AD

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