the demand curve for a perfectly competitive firm is
The demand curve for the output produced by a perfectly competitive firm is perfectly elastic at the going market price. The firm can sell all of the output that it wants at this price because it is a relatively small part of the market.ach perfectly competitive firm is so small relative to the size of the market that it has no market control, it has no ability to control the price. In other words, it can sell any quantity of output it wants at the going market price. This translates into a horizontal or perfectly elastic demand curve.