物体a,b连体,速率一样都做匀速直线运动,故所受合力都为零.
用隔离法:
向右运动时:对a,f摩=f线拉.
对b,f线拉=Gb=2n
``````````````````````````f摩=f线拉=Gb
同理向左运动时:
对a,F=f摩+f线拉
对b,f线拉=Gb
`````````````````````````F=4n
物体a,b连体,速率一样都做匀速直线运动,故所受合力都为零.
用隔离法:
向右运动时:对a,f摩=f线拉.
对b,f线拉=Gb=2n
``````````````````````````f摩=f线拉=Gb
同理向左运动时:
对a,F=f摩+f线拉
对b,f线拉=Gb
`````````````````````````F=4n