The market price will rise to the level where firms in the market are making normal profits in the long run. Existing firms must not be suffering losses. Existing firms must not be earning profits. Firms must be producing at the minimum point of the LRAC curve. Graph insert here.
Technological change occurs as a single isolated event.
A technological development shifts downward the cost curves of newly built plants. Over time those new plants are built and firms enter the market. Technological change occurs continuously Technological change occurs continuously each year new plants have lower cost curves than plants built the previous year. Price in the market is determined at the min ATC of the most efficient plants. The appeal of perfect competition is that no individual firm or consumer wields any economic power in a perfectly competitive market.