把路程分成兩部分,看成兩個(gè)初速為0的勻加速運(yùn)動(dòng)
設(shè)：s1,s2,a1,a2,v(max)
s1=1/2*a1*t1^2.(@)
s2=1/2*a2*t2^2
t1=v(max)/a1.(1)
t2=v(max)/a2.(2)
s1+s2=s.(3)
s1/s2=(a1/a2)*(t1/t2)^2
由（1）,（2）得,
a1/a2=t2/t1所以,s1/s2=t1/t2
t1/t2=5/2.(4)
由（3）,（4）得,
s1=2500m
s2=1000m
將s1,t1代入（@)得,
a1=5/90(m/s^2)
v(max)=a1*t1=50/3(m/s)