When casting the cast-iron part of the machine, voids were formed inside, in order to determine the volume

When casting the cast-iron part of the machine, voids were formed inside, in order to determine the volume of these voids, the casting was weighed and its outer volume was determined as 4.2 cubic meters and the mass was 27.3 kg. What is the volume of the voids?

Data: V (outer volume of the obtained casting) = 4.2 dm3; m (casting weight) = 27.3 kg.

Constants: ρh (density of cast iron) = 7000 kg / m3.

1) Determine the actual volume of the resulting casting: Vf = m / ρh = 27.3 / 7000 = 0.0039 m3 = 3.9 dm3.

2) Calculate the volume of voids: Vp = V – Vf = 4.2 – 3.9 = 0.3 dm3.

Answer: The volume of voids formed in the casting is 0.3 dm3.