[tex]\displaystyle Se~da:\\ \\
l=10cm=0,1m\\ \\
\rho=2,7\frac{g}{cm^3}=2700\frac{kg}{m^3}\\ \\
a)g=10\frac N{kg},~F_{el}=?N\\ \\
b)k=100\frac{N}{m},~\Delta l=?m\\ \\ \\
Formule:\\ \\ a)F_{el}=G\\ \\ \\
G=m\times g\\ \\ \\
m=V\times\rho\\ \\ \\
V=l^3\Rightarrow m=l^3\times\rho\Rightarrow G=l^3\times \rho\times g\Rightarrow F_{el}=l^3\times \rho\times g[/tex]
[tex]\displaystyle b)F_{el}=k\times \Delta l\Rightarrow \Delta l=\frac{F_{el}}{k}\\ \\ \\
Calcule:\\ \\
a)F_{el}=0,1^3\times 2700\times 10=27N\\ \\
b)\Delta l=\frac{27}{100}=0,27m[/tex]
