Answer to Question #29178 in Quantum Mechanics for betelhem

Question

a woman weighs 475 N and a downward force of 17 N must be applied to keep her completely submerged in water what is the density of her body

Answer 1

The buoyance force acting by water upon the woman is
F = rho_o * g * V,
where rho_o is the density of water, and V the volume of thewoman.
By the 3rd Newton's law, the same force is applied downwardsto compensate for the buoyance force, so it's 17 N by magnitude.
The woman's weight is P = m * g = rho_n * g * V, where rho_nis the density of the woman.

From these equations,
rho_n = P / (g*V) = rho_o * P/F = 1000 (kg/m^3) * 475 N / 17N = 27 941 kg/m^3.