2min=120s.36km/h=10m/s设水的流速为xm/s木箱落水后,船和木箱背向行驶,所以2min后他们相距(x+10-x)×120=1200m发现后船追木箱,因为发现后木箱离桥的距离为120x,船追木箱所用时间t=1200/(x+10-x)=120s=2min所以木箱走...能不能用追及问题关系式解我用了.在t=1200/(x+10-x)=120s=2min这里用了