What does a supply curve show?

Question

BlackTom AI · Accepted Answer

The law of supply states that, ceteris paribus, sellers are willing to produce and offer more of a good at higher prices, so the supply curve slopes upward.

1. Relevant knowledge points and concepts
- Law of supply: as price rises, quantity supplied rises (holding other factors constant).
- Supply curve: graphical representation of the relationship between price (vertical axis) and quantity supplied (horizontal axis).
- Ceteris paribus: other determinants (technology, input costs, taxes) are held constant when interpreting the curve.

2. Step-by-step reasoning
- A supply curve plots combinations of price and the quantity producers will supply.
- If price increases, producing and selling the good becomes more profitable, so more firms enter or existing firms increase output, raising quantity supplied.
- Therefore the relationship depicted is positive (both price and quantity supplied move in the same direction).

3. Example calculation / intermediate steps
- Suppose at price $5 a firm supplies 100 units. At price $7 the firm supplies 150 units.
- Change in price = $7 − $5 = $2.
- Change in quantity supplied = 150 − 100 = 50 units.
- Both price and quantity supplied increased, demonstrating a positive relationship.

4. Why the correct answer is correct
- Option d states a positive relationship between price and quantity supplied, which directly restates the law of supply and corresponds to an upward-sloping supply curve on a standard price-quantity graph.

5. Why the other options are incorrect
- a. "A negative relationship between price and quantity supplied" contradicts the law of supply (it would describe a downward slope, which is not typical for supply).
- b. "A negative relationship between price and quantity demanded" describes the law of demand, not the supply curve.
- c. "A positive relationship between price and quantity demanded" is generally false (demand is usually negatively sloped; only rare exceptions like Veblen or Giffen goods deviate).

6. Conclusion
- The supply curve shows a positive relationship between price and quantity supplied; therefore the correct answer is d. A positive relationship between price and quantity supplied.

What does a supply curve show?单项选择题

类似问题

The bond supply curve is sloping, indicating a relationship between price and quantity supplied: