What is the relationship between the bowed out shape of the production possibilities frontier and the increasing opportunity cost of a good as more of it is produced?

What will be an ideal response?

The production possibilities frontier is bowed out because the opportunity cost of a good increases as more of it is produced. As the first unit of the good measured along the horizontal axis is produced, resources that are extremely well suited for its production can be used. Because of the suitability, not many resources need to be devoted to its production, so the opportunity cost—the decrease in the production of the good measured along the vertical axis—is not large. At this location along the production possibilities frontier, the slope of the production possibilities frontier is shallow. But, as more of the product is produced, resources that are not as well suited must be devoted to its production. Consider one of the last units of this good, just before the production possibilities frontier intersects the horizontal axis. By the time the nation produces this much of the product, to produce one more unit means that resources that are extremely poorly suited in its manufacture must be used. Because these resources are not well suited, a lot of them must be used and, because a lot of them must be used, the opportunity cost in terms of the forgone other good is large. With the large decrease in the production of the good along the vertical axis, the slope of the production possibilities frontier at this location is steep . So, the production possibilities frontier goes from having a shallow slope to a steep one, that is, the production possibilities frontier is bowed outward.