问问一道物理题2

  (1)  a=f/m=mgu/m=ug=0.32*10 (m/s<2>)=3.2  (m/s<2>) （2）v=120km/h=33.3m/s     s1=vt1=33.3*0.6m=200m   (3)     t2=v/a=33.3/3.2s=10.4s     s2=v*t2/2=173m     s=s1+s2=373m