In microeconomics, supply and demand is an economic model of price determination in a market. Supply and demand trading pdf it is normal to regard the quantity demanded and the quantity supplied as functions of the price of the goods, the standard graphical representation, usually attributed to Alfred Marshall, has price on the vertical axis and quantity on the horizontal axis. By contrast, responses to changes in the price of the good are represented as movements along unchanged supply and demand curves.
A supply schedule is a table that shows the relationship between the price of a good and the quantity supplied. Under the assumption of perfect competition, supply is determined by marginal cost. That is, firms will produce additional output while the cost of producing an extra unit of output is less than the price they would receive. A hike in the cost of raw goods would decrease supply, shifting costs up, while a discount would increase supply, shifting costs down and hurting producers as producer surplus decreases.
This is true because each point on the supply curve is the answer to the question “If this firm is faced with this potential price, how much output will it be able to and willing to sell? If a firm has market power, its decision of how much output to provide to the market influences the market price, therefore the firm is not “faced with” any price, and the question becomes less relevant. Economists distinguish between the supply curve of an individual firm and between the market supply curve. The market supply curve is obtained by summing the quantities supplied by all suppliers at each potential price.