Question

What is the relationship of a single firm's demand curve in a purely competitive industry?

Answer 1

Pure competition or perfect competition is where all firms have full knowledge of what is going on in the market, where there is free flow of information between not only the producers, but also with the consumers.

As such, all firms have no dominant share of market power since each individual firm is able to produce the good of the same quality and quantity (factors of production are fluid, and no costs in transportation in this theory). And at the same time, consumers have full knowledge of the quality of good they are getting and hence no firm will be able to exploit the misinformation of a good for its own profits.

This builds up to the point of a perfectly elastic demand curve, where consumers know what amount and at which price point do they value the product at. And knowing for the fact that small individual firms in a purely competitive firm have no say over prices, they become the price takers for this kind of market. Thus where MB=MC, the equilibrium point is reached and it is also at the socially optimal level since all consumers have full knowledge of the pros and cons of consuming a product (hence no externalities).

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