A metal rod of length 2 meters and diameter 1.5 centimeters has mass 2.827 kilograms. What is its density in kilograms per cubic meter?

Answer 1

The volume of a cylinder is calculated from the equation:

Converting the diameter of 1.5 cm into a radius in meters, we divide it by 100 (there are 100 cm in one meter). 1.5/100 and divide by 2 = 0.0075 meters

V = π(0.0075²)(2) =3.5343x10^-4 m³

Density = mass/volume = 2.827/(3.5343x10^-4) = 7998.8 kg/m³ the number of sig figs in the "givens" is one therefore we round the answer to 1 sig fig.

ρ = 8000 kg/m³