Editing Price elasticity of supply (section)

==Short-run and long-run==
Since firms typically have a limited capacity for production, the elasticity of supply tends to be high at low levels of quantity supplied and low at high levels of quantity supplied. At low levels of quantity supplied, firms typically have substantial capacity available for use, so small increases in price make it profitable for firms to begin to use this idle capacity. Thus, the responsiveness of quantity supplied to changes in price is high in this region of the supply curve. However, as capacity becomes fully utilised, increasing production requires additional investment in capital (for example, plant and equipment). Since the price must rise substantially to cover this additional expense, supply becomes less elastic at high levels of output.