Question

Ce energie cinetica are unmotociclist cu masa de 200Kg cand ruleaza cu viteza de 144 km pe ora

Answer 1

E=m*v^2=200*20736=4147200 J

Answer 2

$m=200 \ kg \\ v=144 \ km/h=40 \ m/s \\ \boxed{E_c-?} \\ \bold{Rezolvare:} \\ \boxed{E_c=\frac{m \cdot v^2}{2}} \\ E_c=\frac{200 \ kg \cdot (40 \ m/s)^2}{2} \\ E_c=\frac{200 \ kg \cdot 1 \ 600}{2} \\ E_c=\frac{320 \ 000 \ J}{2} \\ \Rightarrow \boxed{E_c=160 \ 000 \ J}$