A sample of an unknown material appears to weigh 275 N in air and 160 N when immersed in alcohol of specific gravity 0.700. What is the volume of the material? What is the density of the material?

Answer 1

W(alc) =W(air)-F(buoyant) = W(air)-ρVg
V={W(air)-W(alc)}/ρg=
={275-160}/0.7•9.8 =16.8 m³
W(air) =mg =ρ₀Vg
ρ₀=W(air)/ Vg = 275/16.8•9.8 =1.67 kg/m³