A body of volume V and density ρ  is initially submerged in a liquid of densityσ . If it is lifted through a height h in the liquid, its potential energy will

Resultant downward force on the body is F=Vρg−Vσg=V(ρ−σ)g When it is lifted up thenWork done = Force ×  Distance ⇒  W=V(ρ−σ)gh So, potential energy increases by hV(ρ−σ)g