Explicație:
72 km/h = 72000/3600= 20 m/s
Ec autoturism = m×v^2 /2 =1000 kg × 20^2 m/s /2 = 200000 J
36 km/h = 36000/3600 = 10 m/ s
5t = 5000 kg
Ec camion = m× v^2/2 = 5000 kg×10^2 m/s/2 = 250000 J
200000<250000 => Ec camion > Ec autoturism
