Define equilibrium price of good .what factor leave to shift in ppc

The equilibrium price is the price at which demands equals supply. It is the price at which there are neither unsatisfied buyers nor unsatisfied sellers. The equilibrium price can not change unless demand or supply schedules change. PPC can shift due to the change in endowment of resources and change in the production technology.  In case of the increase in the resource availability/technological advancement the initial PPC will shift outwards to the new PPC. On the contrary, decrease in the resource availability/outdating technology is represented by an inward shift of the initial PPC