This chapter discusses how firms operate under perfect competition, focusing on profit maximization and supply curves.
The Theory Of The Firm Under Perfect Competition - Quick Look Revision Guide
Your 1-page summary of the most exam-relevant takeaways from Introductory Microeconomics.
This compact guide covers 20 must-know concepts from The Theory Of The Firm Under Perfect Competition aligned with Class 12 preparation for Economics. Ideal for last-minute revision or daily review.
Complete study summary
Essential formulas, key terms, and important concepts for quick reference and revision.
Key Points
Perfect Competition Defined
Many buyers and sellers with homogenous products. No individual can influence prices.
Price-Taker Behavior
Firms accept market price; can't charge more. Selling above leads to zero sales.
Total Revenue (TR) Formula
TR = p × q; total revenue equals price per unit multiplied by quantity sold.
Average Revenue (AR) Equals Price
For price-taking firms, AR = TR/q = p, indicating price equals average revenue.
Marginal Revenue (MR) Equals Price
For price-taking firms, MR = change in TR/change in quantity equals market price.
Profit Maximization Condition
Optimal output (q*) occurs when MR = MC. For perfect competition, P = MC.
Profit Calculation
Profit (π) = TR - TC; determined by revenue minus total costs incurred.
Short-run Supply Curve
Rising part of the SMC curve above minimum AVC and zero for prices below AVC.
Long-run Supply Curve
Rising part of the LRMC curve above minimum LRAC and zero below LRAC.
Shut Down Point
Short-run: firm produces if P ≥ AVC. Below this, firm stops production.
Normal Profit vs. Super Normal Profit
Normal profit is a firm's minimum requirement to continue; super-normal is excess profit.
Impact of Input Prices on Supply
Increase in input prices shifts supply curve left; production costs rise.
Technological Progress Effects
Improves efficiency, reduces costs, shifts supply curve right; more output at same prices.
Unit Tax on Supply Curve
Imposing a tax raises costs, shifts the supply curve left; firms supply less.
Market Supply Curve
Aggregated supply from all firms at various price levels; horizontal summation of individual curves.
Price Elasticity of Supply
Measures responsiveness of quantity supplied to price changes; eS = (%ΔQd) / (%ΔP).
Breakeven Point
Where TR equals TC, or firm earns normal profit; firm continues to operate without losses.
Demand Curve Facing Firm
Perfectly elastic demand due to availability of perfect substitutes; horizontal at market price.
Market Changes Affecting Firms
Changes in the number of firms in the market shift the supply curve; more firms shift right.
Short-run vs Long-run Decisions
Short-run, firms can cover variable costs; in long-run, must cover all costs including opportunity costs.
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