[tex]m=30 \ kg \\ k=1 \ 500 \ N/m \\ g=10 \ N/kg \\ \boxed{\triangle l-?} \\ \bold{Rezolvare:} \\ \boxed{G=m \cdot g} \\ \boxed{k= \frac{F_e}{\triangle \ l}} \\ \Rightarrow \triangle l = \frac{F_e}{g} \\ F_e=G=m \cdot g \\ F_e=G=30 \ kg \cdot 10 \ N/kg \\ F_e=300 \ N \\ \triangle l= \frac{300 \ N}{1 \ 500 \ N/m} \\ \Rightarrow \boxed{\triangle l=0,2 \ m}.[/tex]
