U-Tube Differential Manometer

To determine the pressure difference between point A and B, start from one end and work to the other end:

     p_A - ρ₁gh₁ - ρ₂gh₂ + ρ₁g (h₁ + h₂) = p_B

Rearrange terms to yield:

     p_A - p_B = gh₂ (ρ₂ - ρ₁)

For the given values of ρ₁ = 1000 kg/m³, ρ₂ = 1600 kg/m³ and h₂ = 0.75 m:

     p_A - p_B = (9.8 m/s²) (0.75 m) (1600 - 1000) kg/m³
                 = 4.4 kPa