Question

cat este energia cinetica a unui autocamion gol,avand masa de 5 tone,când are viteza 54km\h? dar cand este incarcat cu inca 5tone de marfă,la aceeasi viteza?

Answer 1

m1=5t--->m1=5.000kg
v=54km/h---->v= 15m/s
m2=m1+5t--->5.000t+5.000t= 10.000kg
Ec=?
Ec1=
$Ec1= \frac{mv^{2}}{2} = \frac{5.000kg*225m^{2}/s^{2}}{2} =562.500J$
Ec2=$\frac{m_{2} *v^{2}}{2} = \frac{10.000kg*225}{2} = 1125*10^{3} J$