一辆汽车以20m/s的速度匀速行驶了3km 然后停了50min 接着又在400s内前进5.5km 则汽车在全程的平均速度
1个回答

那我也改:

t1 = S1 / v1 = 3000 / 20 = 150s

t2 = 5min = 300s

t3 = 400s

t总 = t1 + t2 + t3 = 850s

S总 = 3000m + 5500m = 8500m

v平均 = S总 / t总 = 8500 / 850 = 10m/s