A.10N,30N,80N | B.10N,30N,30N |
C.0,30N,80N | D.0,30N,30N |
A.当卡车启动时,卡车对集装箱的静摩擦力使集装箱随卡车一起运动,方向向前 |
B.卡车匀速运动时,卡车对集装箱的静摩擦力使集装箱随卡车一起运动,方向向前 |
C.当卡车匀速运动时,卡车对集装箱的摩擦力为零 |
D.当卡车刹车时,卡车对集装箱的静摩擦力为零 |
A.15N,30N,40N | B.0N,15N,15N |
C.0N,20N,40N | D.15N,40N,40N |
A.10N,2N | B.0N,8N |
C.2N,2N | D.0N,2N |
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