Short Run

Definition

The short run is a period of time in which at least one factor of production is fixed, while other factors can be varied. This concept is particularly important in the analysis of costs, as it helps distinguish between the behavior of costs in the short run versus the long run.

5 Must Know Facts For Your Next Test

1. In the short run, a firm can only increase output by increasing the use of variable inputs, as at least one factor of production is fixed.
2. As output increases in the short run, variable costs rise, but fixed costs remain constant, leading to changes in the firm's cost structure.
3. The law of diminishing returns states that as more variable inputs are added to a fixed input, the marginal product of the variable input will eventually decrease.
4. Short-run cost curves, such as average cost and marginal cost, are U-shaped due to the interplay of fixed and variable costs.
5. The short run is a crucial concept in understanding a firm's production and cost decisions, as it helps analyze how costs change with changes in output.

Review Questions

• Explain how the distinction between fixed and variable costs is important in the short run.
  • In the short run, a firm can only increase output by increasing the use of variable inputs, as at least one factor of production is fixed. This means that variable costs will rise with increased output, while fixed costs remain constant. The interplay between fixed and variable costs is what leads to the U-shaped nature of short-run cost curves, such as average cost and marginal cost. Understanding this distinction is crucial for a firm to make optimal production and cost decisions in the short run.
• Describe the relationship between the law of diminishing returns and short-run costs.
  • The law of diminishing returns states that as more variable inputs are added to a fixed input, the marginal product of the variable input will eventually decrease. This has important implications for short-run costs. As a firm increases output by adding more variable inputs to the fixed input, variable costs will rise at an increasing rate due to diminishing returns. This, in turn, leads to the U-shaped nature of short-run cost curves, where average and marginal costs first decrease and then increase as output expands in the short run.
• Analyze how the concept of the short run allows firms to make more informed production and cost decisions.
  • The distinction between the short run and the long run is crucial for firms to make informed production and cost decisions. In the short run, at least one factor of production is fixed, which means firms can only increase output by increasing the use of variable inputs. This understanding of the short-run cost structure, with its fixed and variable cost components, allows firms to better predict how their costs will change as output changes. Firms can then use this information to optimize their production levels, minimize costs, and make more informed strategic decisions, ultimately improving their overall performance and profitability.

Related terms

Fixed Costs: Costs that do not change with the level of output in the short run, such as rent, insurance, and certain equipment expenses.

Variable Costs: Costs that change with the level of output in the short run, such as raw materials, labor, and energy expenses.

Total Costs: The sum of fixed costs and variable costs, representing the total amount a firm must pay to produce a given level of output.