Answer to Question #51664 in Macroeconomics for Dipankar sonowal
How do you reconcile the dif
ference in the shape of the
curve in the short run and the long run
The shape of a typical firm’s short-run and long-run ATC curves may in fact be identical. But there are some very important differences to understand about the short-run costs and long-run costs faced by firms. The Short-Run: we define the short-run as the period of time over which a firm’s plant size is fixed. The only variable resource is labor and raw materials, meaning that when demand increases for a firm’s product, the firm is able to increase employee work hours, hire more workers and use existing capital more intensively, but it does not have the time to acquire new capital or expand factory size. Likewise, when demand falls for a firm’s products, it can cut back on work hours, fire workers, but cannot downsize its plants or factories. The Long-Run: The long-run is defined as the variable-plant period. A firm can adjust the number of all its inputs: land, labor and capital. One way of thinking about the difference between the short-run and the long-run is imagining the long-run as several different short-runs spread out over a larger range of output. When we examine the long-run ATC more closely, it becomes apparent that there are in fact lots of little short-run ATC curves along the length of the long-run curve. Each of the gray lines in the graph above represent a short-run period in which this firm opened a new factories.