For permanent magnet we require “High retentivity” (to make magnet strong) and “High coercivity” (magnetisation should not be wiped away easily). Sample ‘P’ have both high retentivity and high coercivity. For electromagnet we require “High saturated magnetism” (to develop high magnetisation) “ low coercivity” (so that it can easily demagnetize) and “least possible area of hysteresis loop” (energy loss in magnetisation is least) Sample ‘Q’ is suitable for Electromagnet.