En un recipiente con mercurio (13.6 gr/cm3) se sumerge completamente un cuerpo de 900 gramos de masa. AL medir su peso aparente este marca 2.94 newton en el dinamómetro. Cual es la densidad del cuerpo (kg/m3)

Respuesta :

Answer:

      ρ = 20.4 kg / m³

Explanation:

For this exercise we use Archimedes' principle, the thrust on a submerged body is equal to the weight of the released liquid

           B = ρ g V_liquid           (1)

let's write the equilibrium equation

           F -W + B = 0

           B = W -F

let's calculate

           B = 0.900 9.8 - 2.94

            B = 5.88 N

From equation 1

            V_{liquid} =  [tex]\frac{B}{\rho_{Hg} g}[/tex]

            V_{liquid} = [tex]\frac{5.88}{13.6 \ 10^3 \ 9.8}[/tex]

            V_{liquid} = 4.41176 10⁻⁵ m³

       

in this case it is indicated that the body is completely submerged

           V_body = V_liquid = V

     the definition of density is

           ρ = m / V

           ρ = [tex]\frac{0.900 \ 10^{-3}}{ 4.41176 \ 10^{-5} }[/tex]

           ρ = 2.04 10¹ kg / m³

           ρ = 20.4 kg / m³