Question

The specific gravity of ethyl alcohol is 0.79. Calculate its specific weight (in both pounds per cubic foot and kilonewtons per cubic meter) and mass density (in both slugs per cubic foot and kilograms per cubic meter). 

Answer 1

Specific gravity =0.79

g=9.8m/sec²

Specific weight

FPS system

$$w_t=\rho g=0.79\times62.4=49.3lb/ft^3$$

Specific weight

MKS system

$\gamma=0.79\times9.79=7.73kN/m^3$

Mass density

FPS

$\rho=1000kg/m^3\\\rho=62.4lbs/ft^3$

$$\gamma=\rho g=0.79\times1.94=1.53slung/ft^3$$

MKS

$$w_t=\rho g=0.79\times1000=790kg/m^3$$