Final answer:
The expected corresponding dimension of a polystyrene molding cannot be calculated without specific shrinkage rates,
Step-by-step explanation:
The correct answer is option - to determine the expected corresponding dimension of a polystyrene molding made in the same mold as a polyethylene part, one must consider the shrinkage properties of the polymers. Injection molding is a common process for manufacturing plastic parts where material shrinkage can affect the final dimensions.
The dimensional change when switching materials like from polyethylene to polystyrene is influenced by differences in thermal expansion and shrinkage rates of the materials.
Without specific shrinkage rates provided, the exact dimension of the polystyrene molding cannot be calculated here. Typically, material data sheets will list a material's shrinkage rate, which can range from 0.5% to 2% or more.
Polyethylene and polystyrene have different shrinkage rates due to their molecular structures and thermal properties. To find the expected dimension, engineers apply the shrinkage rate to the mold dimensions before manufacturing.
For precise molding, engineers also consider factors like the cooling rate, crystallinity of the polymer, and processing conditions.
Without the exact shrinkage rate for polystyrene, we assume it to be different than that of polyethylene, suggesting that the resulting polystyrene part will differ in size from the original 3.000 inches dimension.