A rectangular channel is 4.0 m wide and carries a discharge of 2.0 m3/s with a depth of 0.4 m. The channel transitions to a maximum width contraction at a downstream location, without influencing the upstream flow conditions. The width (in meters) at the maximum contraction is ______________ (rounded off to 2 decimal places).
A 5 m × 5 m closed tank of 10 m height contains water and oil, and is connected to an overhead water reservoir as shown in the figure. Use $\gamma_w$ = 10 kN/m³ and Specific gravity of oil = 0.8.
The total force (in kN) due to pressure on the side PQR of the tank is _______________ (rounded off to the nearest integer).
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If 5cm3 of water is added to the right limb, the new height (in cm, up to two decimal places) of mercury in the LEFT limb will be______
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