GATE 2016 ME (ME1) – Question 49

Fluid Mechanics · Fluid properties, fluid statics, forces on submerged bodies, stability of floating bodies · 2 marks · Numerical answer

An inverted U-tube manometer measures the pressure difference between pipes A and B as shown. Pipe A carries oil of specific gravity 0.8 and pipe B carries water. Air and water densities are 1.16 and 1000 kg/m³. With g = 10 m/s², the pressure difference between A and B is ______ kPa.

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Correct answer: -2.21 to -2.19 OR 2.19 to 2.21

Explanation

Move upward0.20m in oil from A, upward0.08m in air, then downward0.38m in water to B. This gives pB=pA−800·10·0.20−1.16·10·0.08+1000·10·0.38. Therefore pA−pB=**−2.199072kPa**. The official key also accepts the opposite sign convention, +2.199072kPa; both disjoint ranges are retained.