Question 1

Why is the long-run aggregate supply curve vertical?

Accepted Answer

The LRAS curve is vertical because in the long run, output depends on resources, technology, and productivity—not price levels. When prices double, wages and input costs also double, leaving real profit margins unchanged. Firms lack incentive to exceed normal capacity, so production remains at the full-employment level regardless of inflation.

Question 2

What determines the position of the long-run aggregate supply curve?

Accepted Answer

The LRAS position is determined by the economy's maximum sustainable output, which depends on workforce size, capital quality, labor skill levels, and technology. These factors establish the full-employment level of production. The curve represents the economy's efficient, sustainable output capacity that remains stable regardless of price changes.

Question 3

How does the long-run aggregate supply curve differ from the short run?

Accepted Answer

In the long run, all prices including wages and materials fully adjust, making output independent of price levels. The LRAS is vertical at potential output. In contrast, the short run allows sticky prices and wages, permitting output to vary with price changes. Long-run equilibrium reflects sustainable production capacity.

Question 4

Why don't higher prices cause firms to increase production in the long run?

Accepted Answer

Higher prices alone don't increase production because input costs rise proportionally in the long run. When a construction company sees housing prices increase, wages and material costs like cement and steel also rise. Real profit margins remain unchanged, eliminating incentive to expand beyond existing capacity.

Question 5

What role does full employment play in the long-run aggregate supply curve?

Accepted Answer

Full employment represents the maximum sustainable output level where all resources are optimally utilized. The LRAS curve is positioned at this full-employment output level. Once input markets reach equilibrium and prices adjust completely, the economy operates at this capacity, which remains constant regardless of price fluctuations.

Question 6

How does the long-run aggregate supply curve explain sustainable economic growth?

Accepted Answer

The LRAS shows that lasting economic growth depends on real improvements like better skills, more tools, and stronger technology—not just higher prices. Sustainable progress requires strengthening the economy's foundations through increased resources and productivity. Price increases alone cannot shift the LRAS or expand the economy's production capacity.

Question 7

What happens to real profit margins when the price level doubles in the long run?

Accepted Answer

Real profit margins remain unchanged when prices double because input costs also double. Workers demand double wages and suppliers demand double prices for materials to maintain purchasing power. Since manufacturers pay double for inputs while selling goods at double prices, their real earnings and incentives to produce stay constant.

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