Question

h=5 m
g=10N\kg
Ff= 0
v( viteză )=?.......VA ROOG IMI TREBUIE MAINE !

Answer 1

$h=5 \ m \\ g=10 \ N/kg \\ E_c=E_p \\ \boxed{v-?} \\ \bold{Rezolvare:} \\ \boxed{E_c=\frac{m \cdot v^2}{2}} \ \ \ \ \boxed{E_p=m \cdot g \cdot h} \\ E_c=E_p \ \ \Rightarrow \frac{m \cdot v^2}{2}=m \cdot g \cdot h \\ \Rightarrow \frac{v^2}{2}=g \cdot h \\ \Rightarrow v^2=2 \cdot g \cdot h \\ v^2=2 \cdot 10 \ N/kg \cdot 5 \ m =10 \ m \cdot 10 \ N/kg \\ v^2=100 \ N/kg \cdot m \\ v=\sqrt{100} \ m/s\\ \Rightarrow \boxed{v=10 \ m/s}$

Answer 2

Din "enunt" inteleg ca un corp cade liber de la 5m fara frecare si se cere viteza de la capatul cursei.
Ep = Ec
mgh = mV²/2   => V² = 2gh
V = √2gh = √100 = 10 m/s