P1 = pressure at section 1 P2 = pressure at section 2 ρ = density of water ρm = density of mercury x = distance h = distance S = Density of mercury Consider Section 1 as datum line (
P1
r
) + x + h = (
P2
r
) + x + Sh + 0.8
P1
r
−
P2
r
−0.8 = (S – 1)h = (13.6 – 1)h = 12.6 h By continuity Q=(