Definitions [11]
Define the concept of demand schedule.
A tabular representation that shows the quantity of a good a consumer is willing to purchase at different prices, over a specific period of time.
- "The demand for anything at a given price is the amount of it which will be bought per unit of time at that price." – Prof. Benham
- "By demand, we mean the quantity of a commodity that will be purchased at a particular price and not merely the desire of a thing." – Hansen
- "The demand for a particular good is the amount that will be purchased at a given price and at a given time." – Veera Anstey
- "Want is effective desire for particular thing which expresses itself in the effort or sacrifice necessary to obtain them." – Peterson
Define the following concept:
Derived demand
When goods are demanded so that they can be used in the production of some other commodity, it is called indirect or derived demand.
Define individual demand.
Individual demand refers to the quantity of the commodity that an individual household is willing to buy at different prices in a given period of time.
Define composite demand.
Demand for goods that have multiple uses is called composite demand.
Define the following concept:
Demand
Demand for a commodity refers to the quantity of a commodity that a consumer is willing and is able to purchase at a particular price at any particular point in time.
The demand for a particular good is the amount that will be purchased at a given price and at a given time.
Define joint demand.
When two or more goods are demanded together, it is called joint demand. It exists when two or more goods are required together to satisfy a particular want. Joint demand is also called complementary demand.
- Marshall: “Amount demanded increases with a fall in price and diminishes with a rise in price, other things being equal.”
- Samuelson: “People buy more at lower prices and less at higher prices, ceteris paribus.”
- Ferguson: “The quantity demanded varies inversely with price.”
Define decrease in demand.
When there is a fall in demand due to changes in factors other than the own price of the commodity, it is called a decrease in demand.
Define contraction of demand (or decrease in quantity demanded).
When the quantity demanded of a commodity falls due to a rise in its own price of the commodity, other factors remaining constant, it is called a contraction of demand or a decrease in the quantity demanded.
Formulae [2]
Demand = Desire + Willingness to Buy + Ability to Pay
Dx = f(Px, Pn, Y, T)
Where Dx = Demand for commodity x,
Px = Price of the commodity x,
Pn = Price of related commodities,
Y = Income of the consumer,
T = Taste.
Theorems and Laws [3]
State and explain the law of demand.
The law of demand was introduced by Prof. Alfred Marshall in his book, ‘Principles of Economics’, which was published in 1890. The law explains the functional relationship between price and quantity demanded.
According to Prof. Alfred Marshall, “Other things being equal, higher the price of a commodity, smaller is the quantity demanded and lower the price of a commodity, larger is the quantity demanded.” In other words, other factors remaining constant, if the price of a commodity rises, demand for it falls and when price of a commodity falls demand for the commodity rises. Thus, there is an inverse relationship between price and quantity demanded. Symbolically, the functional relationship between demand and price is expressed as:
Dx = f (Px)
Where D = Demand for a commodity
x = Commodity
f = Function
Px = Price of a commodity
|
Price of commodity ‘x’ (₹)
|
|
| 50 | 1 |
| 40 | 2 |
| 30 | 3 |
| 20 | 4 |
| 10 | 5 |
As shown in Table when price of commodity ‘x’ is ₹ 50, quantity demanded is 1 kg. When price falls from ₹ 50 to ₹ 40, quantity demanded rises from 1 kg to 2 kgs. Similarly, at price ₹ 30, quantity demanded is 3 kgs and when price falls from ₹ 20 to ₹ 10, quantity demanded rises from 4 kg sto 5 kgs Thus, as the price of a commodity falls, quantity demanded rises and when price of commodity rises, quantity demanded falls. This shows an inverse relationship between price and quantity demanded.

In X axis represents the demand for the commodity and Y axis represents the price of commodity x. DD is the demand curve, which slopes downward from left to right due to an inverse relationship between price and quantity demanded.
State and explain the ‘law of demand’ with its exceptions.
Prof. Alfred Marshall introduced the law of demand in his book, ‘Principles of Economics,’ published in 1890. The law explains the functional relationship between price and quantity demanded.
- Statement of the Law: According to Prof. Alfred Marshall, “Other things being equal, the higher the price of a commodity, the smaller the quantity demanded, and the lower the price of a commodity, the larger the quantity demanded.” Explanation: Other factors remain constant: when the price of a commodity rises, demand for it falls, and when the price of a commodity falls, demand for it rises. Thus, there is an inverse relationship between price and quantity demanded.
- Demand Schedule: The law of demand is explained with the help of the following demand schedule:
Demand Schedule Price of commodity
‘x’ (in ₹)Quantity demanded
per week (in kg)10 1 8 2 6 3 4 4 2 5 - From the above schedule, it can be observed that when the price of the commodity is ₹ 10, the demand is 1 kg.
- When the price falls from ₹ 10 to ₹ 8, the demand rises from 1 kg to 2 kg.
- Similarly, as the price falls from ₹ 8 to 6 and from ₹ 6 to 4, the demand rises from 2 kg to 3 kg and 3 kg to 4 kg, respectively.
- If we look at the schedule from bottom to top, when the price rises from ₹ 2 to ₹ 4, the demand falls from 5 kg to 4 kg.
- Thus, we can conclude that as the price of a commodity falls, the quantity demanded rises, and when the price of the commodity rises, the quantity in demand falls.
- This shows an inverse relationship between price and quantity demanded.
- Demand Curve: The law of demand can be further explained with the help of the following demand curve:

In the above diagram, the Y-axis represents price, and the X-axis represents quantity demanded. DD is the demand curve that slopes downward from left to right. It represents the inverse relation between price and quantity in demand. - Exceptions: The exceptions to the law are as follows:
- Giffen’s paradox: Giffen Goods are inferior or low-quality goods like vanaspati ghee (Dalda), low-quality rice, etc. These are goods whose demand does not rise, even if their price falls. This happens because every person wants to increase their standard of living constantly.
Sir Robert Giffen observed this behaviour related to bread (an inferior good) in England. People had limited money, so they consumed more bread (a cheaper commodity) and less meat (a costlier commodity). He observed that when the price of bread decreased, less bread was demanded than before. The people saved money and used it to purchase meat, and thus, the demand for meat increased. This behaviour is called “Giffen’s paradox”. There is a direct relationship between price and quantity demanded in the case of Giffen goods. The demand curve for Giffen goods slopes upward from left to right. - Speculation: The law of demand does not hold true when people expect prices to rise further. In this case, although prices have risen today, consumers will demand more in anticipation of a further rise in the price. For example, during the epic lockdown in March 2020, people expected the prices of goods to rise in the future. Therefore, they purchased goods in large quantities, even at high prices.
- Habitual Goods: If a person is habituated to or addicted to certain goods, his demand for these goods will continue to be the same even if the price of such goods rises. For example, people addicted to social media like FB, TikTok, Instagram, etc., will not reduce their usage even if the data packs or internet usage rates are increased.
- Illusion of Price: Consumers may believe that high-priced goods are of better quality; therefore, demand for such goods tends to increase with an increase in their prices. For example, expensive branded products are in demand, even at high prices.
- Prestige Goods: Prestige goods are regarded as a status symbol in society. Rich people may demand more of these goods when their prices rise to show off. E.g. Gold, diamonds, expensive watches, luxury cars, etc.
- Fashion: A product that is out of fashion (e.g., keypad phones) will have less demand even if the price falls. A product in fashion (e.g., smartphones) will have a high demand even if the price rises. Thus, it is an exception to the law.
- Ignorance: Sometimes, people buy more of a commodity at high prices due to ignorance. This may happen because the consumer is not aware of the cost of the commodity at other places.
- Necessities: The demand for specific necessities like basic foodstuffs (wheat, salt, dal, etc.) will not change due to a change in their prices.
- Demonstration Effect: The tendency of the low-income group to imitate the consumption pattern of high-income groups is known as the demonstration effect. For example, the T-shirts “Being Human” by Salman Khan are in very high demand despite their high prices.
- Giffen’s paradox: Giffen Goods are inferior or low-quality goods like vanaspati ghee (Dalda), low-quality rice, etc. These are goods whose demand does not rise, even if their price falls. This happens because every person wants to increase their standard of living constantly.
State the law of demand.
The law of demand states the inverse relationship between the price and quantity demanded of a commodity. According to this law, other things being equal, when the price of a commodity increases, its demand falls and when the price falls, demand increases. Note that the law of demand indicates only the 'direction' of change and not the ‘magnitude’ of change in demand. Further, there is no proportionate relationship between price and demand. If the price of a commodity rises by 20%, its demand may fall by any proportion (i.e. by more or less than 20%). Law of demand, thus, is a qualitative concept, as it does not indicate the magnitude of change in demand. It is important to note here that the law of demand states the effect of change in price on demand and not the effect of change in demand on price.
- According to Marshall, “The amount demanded increases with a fall in price and diminishes with a rise in price.”
- According to Bilas, “The law of demand states that other things being equal, the quantity demanded per unit of time will be greater, lower the price and smaller, higher the price.”
The law of demand states that, other things being equal, the quantity demanded of a good rises when its price drops and falls when its price increases. This shows an inverse relationship between a product’s price and the quantity consumers are willing to buy.
Key Points
- Micro demand = individual level; macro demand = whole economy (aggregate) level.
- Both levels must mention price and time for demand to make sense.
- Demand is always a “flow” concept—measured as so much per time period.
- A demand schedule helps predict the quantity consumers will buy at different prices.
- It demonstrates the law of demand: as price falls, demand increases.
- The demand curve is the graphical version of the demand schedule, always sloping downwards.
- Both individual and market schedules are useful for setting prices, planning production, and understanding consumer behaviour.
- Law of Demand: When price drops, quantity demanded increases (other things being equal).
- An individual demand schedule is about one consumer.
- Usually shown with both tables and graphs for better clarity.
- The market demand schedule sums individual demands at each price.
- As price decreases, market demand increases (inverse relationship—law of demand).
- Useful to understand how the overall market reacts to price changes.
- The demand curve represents the law of demand visually.
- There are two types: individual and market demand curves.
- The market demand curve is derived by summing individual curves at each price.
- Movements along the curve are due to price changes; curve shifts are due to outside factors.
- The demand curve for an individual consumer slopes downward from left to right, demonstrating that lower prices lead to higher quantities demanded.
- Demand is affected by individual preferences, income, and prices of related goods (substitutes and complements).
- Only price changes cause movement along the demand curve; other factors cause the curve to shift.
- The market demand curve is the sum of all buyers' demands at each price.
- It slopes downwards: lower price → higher quantity demanded.
- Useful for market analysis and price setting.
The demand curve slopes downward mainly because:
- Lower prices increase demand.
- Explained by utility, income, and substitution effects, more buyers, extra uses, and psychological reasons.
| Type of Demand | Meaning / Explanation | Examples |
|---|---|---|
| Individual Demand | Demand of a single consumer | Demand of one person for a product |
| Market Demand | Sum total of demands of all consumers | Total demand for rice in a market |
| Ex ante Demand | Planned or desired demand | Expected demand for a product |
| Ex post Demand | Actual demand realised in the market | Actual sales of a product |
| Joint Demand | Demand for goods used together | Car and petrol |
| Derived Demand | Demand arising from demand for another good | Labour, raw materials |
| Composite Demand | Demand for goods with multiple uses | Coal, electricity, milk |
| Direct Demand | Demand for goods directly satisfying wants | Food, clothes |
| Alternative Demand | Demand satisfied by alternatives | Rice or chapati |
| Competitive Demand | Demand for substitute goods | Tea and coffee |
- Demand is affected by many factors, not just price.
- A change in any determinant—like income, preferences, or population—can shift demand.
- Some factors (like climate or government taxes) have seasonal or policy-based effects.
- Related goods can be substitutes (used instead) or complements (used with).
- Real-life decisions—like bulk buying before a GST rise—are practical examples of demand determinants at work.
- There is an inverse relation between price and quantity demanded.
- All other factors must remain constant for the law to apply.
- The demand curve always slopes downwards.
- Not all goods follow the law of demand; some have exceptions.
- Giffen and Veblen goods are classic exceptions.
- Be aware of context (exam and real-world) when citing examples.
- Variation in demand occurs due to change in price alone.
- Expansion of demand: Price falls → quantity demanded rises (downward movement on same curve).
- Contraction of demand: Price rises → quantity demanded falls (upward movement on same curve).
- Change in demand occurs due to factors other than price.
- Increase in demand: Demand curve shifts right (favourable factors).
- Decrease in demand: Demand curve shifts left (unfavourable factors).
Important Questions [62]
- Demand for Necessaries is
- Match the Pairs
- State whether the following statement is True or False. Demand for perishable goods is inelastic.
- Demand Curve and Supply Curve.
- Demand for Electricity is Elastic.
- Give Reasons Or Explain the Following Statement Demand for Habitually Used Goods in Inelastic.
- Explain the following concept: Effective demand
- Fill in the Blank Using Proper Alternative Given in the Bracket:Perfectly Inelastic Demand Curve is
- State Whether the Following Statement is True Or False :Demand for Necessary Goods is Inelastic.
- State with Reason. Whether You ‘Agree’ Or ‘Disagree’ with the Following Statement: There Are No Exceptions to the Law of Demand.
- Fill in the Blank with Proper Alternatives Given in the Bracket:Indirect Demand is Also Known as _______ Demand.
- State Whether the Following Statement is True Or False.Perfectly Inelastic Demand Curve is Parallel to ‘X’ Axis.
- Write Short Answer for the Following Question.Explain the Law of Demand.
- Fill in the Blank Using Proper Alternatives Given in the Bracket:Demand for Salt is ...............
- State and explain the law of demand.
- Fill in the Blanks Using Proper Alternatives Given in the Brackets. Demand for Car and Petrol is ____________ De
- Write whether the following statement is True or False: Demand curve has a positive slope.
- Write whether the following statement is True or False: Demand for commodities depends upon various factors.
- Write whether the following statement is True or False: Salt has elastic demand.
- Demand for habitual commodity is ______.
- Define the concept of demand schedule.
- Distinguish Between : Individual Demand Schedule and Market Demand Schedule.
- Write Explanatory Answer. State and Explain the Law of Demand with Its Exception.
- Fill in the blank with appropriate alternatives given in the bracket: The law of demand states ________ relation between demand and price.
- Fill in the Blank with Appropriate Alternatives Given in the Bracket: Demand for Salt is ___________.
- Write Answers in ‘One’ Or ‘Two’ Paras Each. What Are the Main Determinants of Aggregate Demand?
- Explain the Following Concepts Or Give Definitions. Demand
- Distinguish between Desire and Demand.
- Do You Agree with the Following Statement? Give Reason Many Factors Influence the Demand for a Commodity.
- Fill in the Blank Using Appropriate Alternatives Given Below the Demand for Perishable Goods is _______
- State Whether the Following Statement is True Or False:
- There Are No Exceptions to the Law of Demand.
- The relationship between income and demand for inferior goods is ______.
- Define Or Explain the Following Concept.Market Demand .
- The Slope of Demand Curve is ___________ in the Case of Relatively Inelastic Demand. [Flatter/ Steeper/ Horizontal / Vertical]
- State with reasons whether you ‘agree’ or ‘disagree’ with the following statement. Demand curve slopes downward from left to right.
- State with reason, whether you Agree or Disagree with the following statement. The demand curve slopes downward from left to right.
- Explain the law of demand with its assumptions.
- Write Explanatory Notes Or Answer the Following. Aggregate Demand
- State and explain the ‘law of demand’ with its exceptions.
- Fill in the Blank Using Proper Alternative Given in the Bracket:Market Demand is a Total Demand Of...............Buyers.
- Distinguish between: Joint/complementary demand and competitive demand.
- Find the odd word out: Types of demand: Direct demand, Indirect demand, Composite demand, Market demand
- Identify and explain the following concept: Due to mandatory use of masks during corona epidemic the demand for mask producing labour has increased.
- Match the Following Group 'A' with Group 'B': (A) Electricity (1) Joint Demand (B) Perfectly Elastic Demand (2) Lord Keynes (3) Prof. Pigou (C) Aggregate Supply
- The Demand for Salt is _____________
- A Perfectly Inelastic Demand Curve is Parallel to 'Y' Axis.
- Distinguish Between Individual Demand and Market Demand. With the help of diagrams explain the difference between individual demand and market demand.
- Distinguish between the following: Direct demand and Indirect demand.
- Explain with Reason Whether You 'Agree' Or 'Disagree' with the Following Statement: There Are Many Types of Demands.
- Define Or Explain the Concept Perfectly Elastic Demand
- State Whether the Following Statements Are True Or False with Reason: Demand for Medicine is Inelastic.
- Distinguish between Joint demand and Composite demand.
- Define Or Explain the Following Concepts (Any Three): Individual Demand
- Distinguish between expansion in demand and increase in demand.
- Explain any four types of demand.
- Complete the correlation. Direct demand : Food and Mobiles : ______ : Land and Labour.
- Explain with reason, whether you agree or disagree with the following statement. Price is the only determinant of demand
- Symbolically, the functional relationship between Demand and Price can be expressed as ______.
- Explain the law of demand.
- Distinguish between: Expansion of demand and Contraction of demand.
- Explain the concepts of variation and changes in demand with the help of diagrams.
Concepts [14]
- Concept of Demand
- Demand Schedule
- Individual Demand Schedule
- Market Demand Schedule
- Demand Curve
- Individual Demand Curve
- Market Demand Curve
- Reasons for the Downward Slope of the Demand Curve
- Types of Demand
- Determinants of Demand
- Law of Demand
- Exceptions to the Law of Demand
- Variations in Demand
- Changes in Demand
