The Basics of Demand in Microeconomics

Concept: The Basics of Demand

Introduction to Demand

Understanding demand is fundamental in microeconomics, as it describes how buyers behave in a market. Demand analysis typically uses the price-quantity graph to illustrate the relationship between the price of a good and the quantity demanded by consumers.

• Demand refers to the behavior of buyers/consumers in a perfectly competitive market.

• Quantity demanded is the amount of a product that buyers are willing to purchase at a given price.

• The demand schedule lists pairs of prices and quantities demanded, providing a tabular representation of demand.

The Law of Demand

The Law of Demand is a core principle in microeconomics, stating the inverse relationship between price and quantity demanded.

• Law of Demand: When the price of a good rises, the quantity demanded of that good falls.

• This relationship is typically represented as a downward-sloping demand curve on a price-quantity graph.

What Explains the Law of Demand?

Two main effects explain why the demand curve slopes downward:

• Substitution Effect: As the price of a good increases, consumers may substitute it with a cheaper alternative, reducing the quantity demanded of the more expensive good.

• Income Effect: When the price of a good rises, consumers' purchasing power decreases, leading to a reduction in the quantity demanded.

Demand Curve and Demand Schedule

The demand curve graphically shows the relationship between the price of a good and the quantity demanded. The demand schedule provides the same information in tabular form.

• The demand curve is typically downward sloping, reflecting the Law of Demand.

• Each point on the curve corresponds to a price-quantity pair from the demand schedule.

Price (per unit)	Quantity Demanded
$50	12,000
$40	24,000
$30	36,000
$20	48,000
$10	60,000

Note: Some goods and services may not conform to the Law of Demand, but these exceptions are rare.

Key Equations

• Demand Function: The general form of a demand function is: $Q_d = f(P)$ where $Q_d$ is quantity demanded and $P$ is price.

Example

• If the price of a product decreases from $40 to $30, the quantity demanded increases from 24,000 to 36,000 units, illustrating the Law of Demand.