Lösung:
v(t) = -20/(120)^2 * (t - 120)^2 + 20 = t/3 - t^2/720
a(t) = v'(t) = 1/3 - t/360
a)
a(0) = 1/3 m/s^2
m = -20 / (480 - 360) = -1/6 m/s^2
b)
V(t) = t^2/6 - t^3/2160
s1 = ∫ (0 bis 120) v(t) dt = V(120) - V(0) = 1600 m
s2 = 20 * (360 - 120) = 4800 m
s3 = 1/2 * 20 * (480 - 360) = 1200 m
s = 1600 + 4800 + 1200 = 7600 m