Final answer:
A tougher plastic can be identified by choosing one with a larger area under the stress-strain curve, indicating more energy absorption and greater toughness. Stress and strain are critical for understanding these properties. The correct answer is A) Larger.
Step-by-step explanation:
To choose a tougher plastic, you would select one having a larger area under the stress-strain curve. This area is indicative of the amount of energy a material can absorb before failing, which correlates with toughness. A tough plastic can absorb more energy during deformation, which suggests that it is capable of undergoing more plastic deformation before fracture. The large area under the stress-strain curve represents both the material's strength and its ability to deform plastically, which are both characteristics of toughness in plastics.
Stress and strain are important concepts in materials science, particularly in understanding the mechanical properties of materials such as plastics. Stress is a measure of the internal forces that particles of a material exert on each other, while strain is the measure of the deformation of the material. In the stress-strain curve, the elastic region shows how the material can return to its original state after the stress is removed, but the plastic region shows permanent deformation. Answering the CHECK YOUR UNDERSTANDING question: If objects A and B are heated identically and object A is made of a material with a higher thermal expansion coefficient than B, object A will indeed experience a greater stress than B due to its tendency to expand more under the same heating conditions. Therefore, the correct answer is A) Larger.