LAW OF SUPPLY
Focus Activity
P
Q0
S
What does thistell you about the Law of Supply?
SUPPLY
• Law of Supply• The law of supply states that, ceteris parabis, the
quantity supplied of a good rises when the price of the good rises
• Why?• The promise of increased revenues when prices are high
encourages firms to produce more.
• Market Entry: Rising prices draw new firms into a market and add to the quantity supplied of a good.
• Quantity supplied is the amount of a good that sellers are willing and able to sell
The Supply Curve: The Relationship between Price and Quantity Supplied
• Supply Schedule• The supply schedule is a table that shows the
relationship between the price of the good and the quantity supplied
Ben’s Supply Schedule
Supplied
The Supply Curve: The Relationship between Price and Quantity Supplied
• Supply Curve• The supply curve is the graph of the relationship
between the price of a good and the quantity supplied
Figure 5 Ben’s Supply Schedule and Supply Curve
Price ofIce-Cream
Cone
0
2.50
2.00
1.50
1.00
1 2 3 4 5 6 7 8 9 10 11 Quantity ofIce-Cream Cones
$3.00
12
0.50
1. Anincrease in price ...
2. ... increases quantity of cones supplied.
Changes in the Supply Curve
• Change in Quantity Supplied• Movement along the supply curve• Caused by a change in anything that alters the
quantity supplied at each price
1 5
Price of Ice-Cream Cone
Quantity of Ice-Cream Cones0
S
1.00
A
C$3.00 A rise in the price
of ice cream cones results in a movement along the supply curve.
Change in Quantity Supplied
Shifts in the Supply Curve
• Change in Supply• A shift in the supply curve, either to the left or right• Caused by a change in a determinant other than
price
Shifts in the Supply Curve (N.I.C.E.J.A.G.)
• Natural/Man-Made Phenomenon (weather, strikes, riots)
• Input Costs (raw materials, technology)
• Competition (number of producers)
Shifts in the Supply Curve (N.I.C.E.J.A.G.)
• Expectation of Future Prices (producers supply less if price is expected to rise)
• Profit of goods in joint supply (oil/gas)
• Profit of alternative goods in supply (car manufacturers)
• Gov’t Action (taxes / subsidy)
Figure 7 Shifts in the Supply Curve
Price ofIce-Cream
Cone
Quantity ofIce-Cream Cones
0
Increasein supply
Decreasein supply
Supply curve, S3
curve, Supply
S1Supply
curve, S2
