Supply
Introduced| English | Meaning |
|---|---|
| law of supply/lɔː ɒv səˈplaɪ/ | The tendency for quantity supplied to rise as price rises, with other relevant factors held constant. |
| supply/səˈplaɪ/ | The quantity sellers are willing and able to offer at different prices over a specified period. |
| quantity supplied/ˈkwɒntɪti səˈplaɪd/ | The amount sellers are willing and able to offer at a particular price over a specified period. |
| technology/tekˈnɒlədʒi/ | The application of knowledge, methods and tools to practical tasks. |
| tax/tæks/ | A compulsory payment imposed by government to raise revenue or influence behaviour. |
| subsidy/ˈsʌbsɪdi/ | Financial assistance, usually from government, that reduces costs or supports a particular activity. |
Why higher prices bring more goods
- When the price of a crop doubles, farmers rush to plant more of it. Higher prices reward sellers.
- That is the law of supply 供给定律, the mirror image of demand.
The law of supply states that, other things equal, as price rises:
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Higher price, more supplied — the curve slopes up.
The law of supply 供给
- Supply = the quantity sellers are willing and able to produce at each price.
- Law of supply: as price rises, quantity supplied 供给量 rises — other things equal.
The supply curve slopes up — higher price, more produced.
Demand & supply
Supply slopes up — dearer means more made.
The supply curve slopes ______ because higher prices reward sellers.
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Higher price → more supplied → upward slope.
Movement along the curve
- A change in the good's own price moves you along the supply curve.
- A price rise → an extension of supply; a price fall → a contraction.
A new tax on producing a good will:
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A tax raises costs, so less is supplied at each price — a left shift.
A government subsidy to producers shifts the supply curve to the right.
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A subsidy lowers costs, so more is supplied at each price.
Which shift the supply curve? (Select all that apply.)
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Costs, technology and weather shift supply; own price moves you along it.
Shifts in supply
- Non-price factors shift the whole curve: costs of production, technology 技术, taxes 税收 and subsidies, weather, number of firms.
- Lower costs or a subsidy 补贴 → right shift (more supplied); higher costs or a tax → left shift.
A tax shifts supply left; a subsidy shifts it right. A per-unit tax raises sellers' costs, so they supply less at each price. A subsidy does the opposite.
You've got it
- supply = willing and able to produce at each price
- law of supply: price up → quantity supplied up (curve slopes up)
- costs, technology, taxes/subsidies and weather shift the curve
Write from a supply fall of 12
- At a price of 10 dollars, a new tax cuts quantity supplied from 40 to 28.
- Describe the shift.
At a price of 10 dollars, a new tax cuts quantity supplied from 40 units to 28. What is the change, and which way does supply shift?
40 minus 28 is 12.
What does the tax do to supply?
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The same price now brings 12 fewer units, a leftward shift.