In the derivation of P₁ - P₂ =ρgz, it was assumed that the liquid is incompressible. Why will this equation not be strictly valid for a compressible liquid?

In the derivation of P₁ - P₂ =ρgz, it was assumed that the liquid

1.	In the derivation of P₁ - P₂ =ρgz, it was assumed that the liquid is incompressible. Why will this equation not be strictly valid for a compressible liquid?
Answer» With the assumption that the liquid is incompressible, the density ρ becomes constant and the result is valid. For a compressible liquid, ρ will change as the pressure increase (due to change in volume). So the equation is not completely valid.

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In the derivation of P₁ - P₂ =ρgz, it was assumed that the liquid is incompressible. Why will this equation not be strictly valid for a compressible liquid?

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