a metal cubic block with an edge of 5.0 cm has a mass of 2.7 g. Calculate the density of the cube in SI units
1 m = 100 cm
1 cm = 1 / 100 m = 0.01 m
5 cm = 5 ∙ 0.01 m = 0.05 m
1 kg = 1000 g
1 g = 1 / 1000 kg = 0.001 kg
2.7 g = 2.7 ∙ 0.001 kg = 0.0027 kg
Density:
ρ = m / V
m = 0.0027 kg
V = ( 5 cm ) ³ = ( 0.05 m ) ³ = 0.000125 m ³
ρ = m / V = 0.0027 kg / 0.000125 m ³ = 21.6 kg / m ³