Practice question
Question
A manometer with mercury (ρ\=13.6×103kg/m3) shows a height difference of 0.28m. What is the pressure difference? (Take g\=10m/s2)
Explanation
ΔP = ρgh. ρ = 13.6×103kg/m3, g = 10m/s2, h = 0.28m. ΔP = 13.6×103×10×0.28 = 38080Pa. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 3.8 × 10⁴ Pa. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.