m g (1 - \frac{ρ_{v}}{ρ_{A l}}) < m g (1 - \frac{ρ_{v}}{ρ_{F e}}) \Rightarrow F_{A l} < F_{F e}

${mg(1 - \frac{\rho_v}{\rho_{Al}}) < mg(1 - \frac{\rho_v}{\rho_{Fe}}) \quad\Rightarrow\quad F_{Al} < F_{Fe}}$

Error