Question

The average human has a density of 945 kg/m^3 after inhaling and 1020 kg/m^3 after exhaling, out making any swimming movements, what percentage of the human body would be above the surface in the Dead Sea (a body of water with a density of about 1230 kg/m^3) In each of these cases? (b) Given that bone and muscle are denser than fat, what physical characteristics differentiate -sinkers" (those who tend to sink in water) from "floaters" (those who readily float)? (Select all that apply.) Sinkers tend to have more fat. Floaters tend to have more fat. Sinkers tend to have heavier bones. Floaters tend to have heavier bones. Sinkers tend to be taller. Floaters tend to be shorter.

Answer 1

To float buoyant force acting on person must person's weight i.e B = mg we know rho = m/v so B = rho_liquid of V_displaced now V-diaplaced = V_submerged rho_sea of V_displaced = rho_body of V_total (9) (i) i.e V_submerged/V-total = rho_body/rho_sea = 945 kg/m^3/1230 kg/m^3 = 76.8% After initiating (100 - 76.8) = 23.2% above surface (ii) After exhaling V_submerged/V_total = 1020 kg/m^3/1230 = .829 = 82.9% leaving (100 - 82.9) = 17.1% above surface (b) In general sinker's tend to have less fact (thinner) or have heavier bones hence (2) Floaters tend to have more fat and (3) sinkers tend to have heavier bones are correct options