在 t =1s,(v0 - at*1)^2/R = at
由经过3s,即 t = 4s,(v0 - at*4)^2/R = at*tan30°
联立两式,解出
{R = 7.52102,at = 2.58808},或者 {R = 80.959,at = 0.518847}
经过1s,汽车的法向加速度
an(1) = (7.0 - 2.58808*1)^2/7.52102 = 2.588 m/s^2
或 an(1) = (7.0 - 0.518847*1)^2/ 80.959 = 0.518847 m/s^2