Final answer:
In the short run, adding labor to fixed capital is the only way to increase output. We assume that the quantity of hours people are willing to work remains relatively constant, the labor supply curve does not shift significantly, and there are no major changes in factors affecting the labor market.
Step-by-step explanation:
In the short run, when we assume that capital is fixed, the only way to increase output is by adding more labor. However, there are certain assumptions we make about adding labor to fixed capital in the short run:
- The quantity of hours people are willing to work for a given wage does not change much.
- The labor supply curve does not shift much.
- There are no substantial short-term changes in factors such as the age structure of the labor force or laws affecting the labor market.
By assuming these conditions, we can analyze the relationship between labor and output in the short run.