Practice question
Question
A manometer with ethyl alcohol (ρ\=806kg/m3) shows a height difference of 0.3m. What is the pressure difference? (Take g\=10m/s2)
Explanation
ΔP = ρgh. ρ = 806kg/m3, g = 10m/s2, h = 0.3m. ΔP = 806×10×0.3 = 2418Pa. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 2418 Pa. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.