What is the definition of supply in microeconomics?

In microeconomics, supply refers to the total amount of a specific good or service that is available to consumers. It is typically represented as a supply curve on a graph, showing the relationship between the price of the good and the quantity supplied by producers. The concept of supply is fundamental in understanding how markets function and how prices are determined.

How does the law of supply work in economics?

The law of supply states that, ceteris paribus (all other factors being equal), an increase in the price of a good or service will lead to an increase in the quantity supplied, and vice versa. This is because higher prices provide an incentive for producers to supply more of the good, as they can achieve higher revenue. Conversely, lower prices may discourage production, leading to a decrease in supply.

What factors can cause a shift in the supply curve?

Several factors can cause the supply curve to shift, including changes in production costs, technological advancements, taxes and subsidies, the number of sellers in the market, and expectations of future prices. For example, a decrease in production costs or an improvement in technology can shift the supply curve to the right, indicating an increase in supply at every price level.

How do supply and demand interact to determine market equilibrium?

Supply and demand interact in a market to determine the equilibrium price and quantity. The equilibrium is reached when the quantity supplied equals the quantity demanded. At this point, the market is said to be in balance, and there is no tendency for the price to change. If the market is not in equilibrium, forces will act to move it towards equilibrium, such as price adjustments.

What is the difference between a movement along the supply curve and a shift of the supply curve?

A movement along the supply curve occurs when there is a change in the quantity supplied due to a change in the price of the good, with all other factors remaining constant. In contrast, a shift of the supply curve occurs when there is a change in any other factor affecting supply, such as production costs or technology, leading to a new supply curve at every price level. A shift indicates a change in supply, while a movement along the curve indicates a change in quantity supplied.

Supply Revision Notes & Practice Questions | IB DP Economics

Study Notes

Supply refers to the quantity of a good or service that producers are willing and able to sell at various prices over a given period, ceteris paribus.

Supply — the quantity of a good or service a producer is willing and able to sell at various prices. Example: A farmer supplies 100 kilos of wheat at $5 per kilo.
Law of Supply — states that there is a direct relationship between price and quantity supplied, meaning they move in the same direction. Example: As the price of rice increases from 2 yuan to 5 yuan, the quantity supplied increases from 170 kilos to 300 kilos.
Supply Curve — a graphical representation showing the quantity supplied at various prices. Example: An upward-sloping curve showing more rice supplied as price increases.
Non-price Determinants of Supply — factors other than price that cause the supply curve to shift. Example: Changes in technology or the number of firms.
Law of Diminishing Marginal Returns — in the short run, adding more variable inputs to fixed inputs decreases marginal returns, increasing marginal costs. Example: Adding more workers to a fixed number of machines eventually reduces the additional output each worker contributes.

Exam Tips

Key Definitions to Remember

Supply
Law of Supply
Supply Curve
Non-price Determinants of Supply
Law of Diminishing Marginal Returns

Common Confusions

Confusing movement along the supply curve with shifts of the supply curve
Misunderstanding the difference between individual supply and market supply

Typical Exam Questions

What is the Law of Supply? The Law of Supply states that there is a direct relationship between price and quantity supplied, ceteris paribus.
How do non-price determinants affect supply? Non-price determinants cause the supply curve to shift right or left, indicating an increase or decrease in supply.
What happens to supply when the price of a related good changes? The supply of a good can increase or decrease depending on whether the goods are in joint or competitive supply.

What Examiners Usually Test

Understanding of the Law of Supply and its graphical representation
Ability to distinguish between movements along and shifts of the supply curve
Impact of non-price determinants on supply

Supply

Notes & worked examples

Study Notes & Exam Tips

Study Notes

Exam Tips

AI-marked quiz

Supply — frequently asked questions

Supply

Notes & worked examples

Study Notes & Exam Tips

Exam Tips and Study Notes for Supply

Study Notes

Exam Tips

AI-marked quiz

Supply — frequently asked questions

Frequently Asked Questions about Supply

What is the definition of supply in microeconomics?

How does the law of supply work in economics?

What factors can cause a shift in the supply curve?

How do supply and demand interact to determine market equilibrium?

What is the difference between a movement along the supply curve and a shift of the supply curve?