To determine the long-run equilibrium for each firm's production of kites, we need to find the level of output where marginal cost (MC) equals marginal revenue (MR). In perfect competition, firms maximize their profit by producing at the level where MC = MR.
Given the marginal cost function MC = 0.02q, we equate it to the marginal revenue, which is equal to the market price (P) in perfect competition. So, we have:
0.02q = P
Now, we need to find the price at which the quantity demanded (QD) equals the quantity supplied (QS) in the market. To do this, we set QD equal to QS:
QD = QS
Substituting the demand function QD = 4000 - 1000P into the equation, we get:
4000 - 1000P = QS
Now, we can solve for the price (P):
4000 - 1000P = 0.02q
Simplifying further:
1000P = 4000 - 0.02q
P = (4000 - 0.02q) / 1000
Now, we can substitute the value of P into the equation for MC to find the level of output (q):
0.02q = P
0.02q = (4000 - 0.02q) / 1000
Solving for q:
0.02q = 4 - 0.00002q
1.00002q = 4
q = 4 / 1.00002
q ≈ 3999.8
In the long-run equilibrium, each firm will produce approximately 3999.8 kites.
The long-run supply curve for kites in perfect competition is horizontal at the minimum average total cost (ATC) of the firms. This is because in the long run, firms have enough time to adjust their inputs and optimize their production processes, leading to production at the lowest possible cost.
a. To find the number of kites sold and the number of firms in the kite industry, we substitute the price (P) into the demand function QD = 4000 - 1000P:
QD = 4000 - 1000P
QD = 4000 - 1000(4000 - 0.02q) / 1000
Simplifying:
QD = 4000 - 4000 + 0.02q
QD = 0.02q
Since q represents the output per firm and we know that each firm produces around 3999.8 kites, we can substitute this value:
QD = 0.02 * 3999.8
QD ≈ 79.996
Approximately 80 kites will be sold. To find the number of firms in the kite industry, we divide the total quantity supplied by the output per firm:
QS = 3999.8
Number of firms = QS / q
Number of firms = 3999.8 / 3999.8
Number of firms = 1
b. In the very short run, when it is impossible to manufacture any more kites than those produced for that week, the price of kites will be determined by the demand and supply conditions. With the demand function QD = 5000 - 500P, we can find the equilibrium price:
QD = QS
5000 - 500P = QS
Substituting the supply quantity from above:
5000 - 500P = 3999.8
Solving for P:
500P = 5000 - 3999.8