Question

Ajutor...va rogg .......

Answer 1

$l=10 \ cm=0,1 \ m \\ m=2kg \\ k=1 \ 000 \ N/kg \\ g=10 \ N/kg \\ \boxed{\Delta l-?} \\ \boxed{\rho-?} \\ \bold{Rezolvare:} \\ \boxed{k=\frac{F_e}{\Delta l}} \ \ \ \ \ \ \ \ \boxed{\rho=\frac{m}{V}} \\ \Rightarow \Delta l=\frac{F_e}k} \\ F_e=G=m \cdot g \\ F_e=G=2 \ kg \cdot 10 \ N/kg \\ F_e=20 \ N \\ \Delta l=\frac{20 \ N}{1 \ 000 \ N/m} \\ \Rightarrow \boxed{\Delta l=0,02 \ m=\boxed{2 \ cm}} \\ V=l^3 \\ V=(0,1 \ m)^3=0,1 \ m \cdot0,1 \ m \cdot 0,1 \ m \\ V=0,001 \ m^3 \\ \rho=\frac{2 \ kg}{0,001 \ m^3}$
$\Rightarrow \boxed{\rho=2 \ 000 \ kg/m^3}$