Explain the conditions of perfect competition

Explain the conditions of perfect competition. Why is the demand curve facing a firm under perfect competition is perfectly elastic?

The main conditions of perfect competition are:
(i) Large number of buyers and sellers
(ii) Homogeneous product
(iii) Perfect knowledge
(iV) Perfect mobility of factors of production
(v) Free exit and entry of the firms
(vi) No transport cost
When goods are purchased across different buyers, demand curve of a firm is perfectly elastic (${{E}_{d}}$ = $\infty $) because even the slightest change in price will cause an infinite change in demand. Because of this feature, it is also referred to be an imaginary market form.