Practice question
Question
Water (ρ\=1000kg/m3) flows horizontally at 4m/s with pressure 1.6×105Pa. If the speed increases to 7m/s, what is the new pressure?
Explanation
Bernoulli’s equation: P1+12ρv12 = P2+12ρv22. P1 = 1.6×105Pa, v1 = 4m/s, v2 = 7m/s, ρ = 1000kg/m3. P2 = 1.6×105+12×1000(16−49) = 1.6×105−16500 = 1.435×105Pa. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 1.435 × 10⁵ Pa. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.