Relative Equilibrium of Liquids — Worked Examples
Each problem first checks the physical regime before applying an ideal formula. Translational examples distinguish no-spill, spill, and free-fall limits; rotational examples distinguish fully wetted, spilling, and dry-core conditions.
Horizontally Accelerating Tank without Spillage
An open rectangular tank is long and high and initially contains water to depth . It accelerates horizontally at . Determine the two end depths, check for spilling, and find the maximum bottom gage pressure.
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0 of 3 Steps CompletedSpilled Volume during Horizontal Acceleration
A rectangular tank is long, wide, and high. It initially contains water to depth and accelerates horizontally at . Determine the volume spilled after relative equilibrium is reached.
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0 of 3 Steps CompletedTank Accelerating Vertically Upward
A water tank accelerates vertically upward at . Determine the gage pressure below its open free surface.
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0 of 2 Steps CompletedTank Accelerating Vertically Downward
A water tank accelerates vertically downward at . Determine the gage pressure below its open free surface and identify the free-fall limit.
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0 of 3 Steps CompletedAbsolute Pressure during Ideal Free Fall
During an idealized free-fall interval, a connected pressure boundary fixes a liquid at absolute. The container and liquid accelerate downward at , and other effects are neglected. What absolute pressure exists at a point vertically away within the connected liquid?
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0 of 2 Steps CompletedCombined Horizontal and Upward Acceleration
A long tank accelerates horizontally at while accelerating upward at . Determine the free-surface angle magnitude and end-to-end elevation difference.
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0 of 3 Steps CompletedRotating Open Cylindrical Tank without Spillage
A cylindrical tank is in diameter and high and initially contains water to depth . It rotates at . Determine center and wall depths and check for spilling or bottom uncovering.
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0 of 3 Steps CompletedRotational Speed for Incipient Spillage
An open cylindrical tank has radius , height , and initial water depth . Assuming the surface vertex remains above the tank bottom, determine the speed at which the wall first reaches the rim.
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0 of 3 Steps CompletedOnset of a Dry Central Region before Spillage
A cylindrical tank has radius , height , and initial liquid depth . Determine the angular speed at which the rotating free-surface vertex just reaches the tank bottom. Verify that the wall is still below the rim at that instant.
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0 of 3 Steps CompletedRadial Pressure Difference in a Closed Rotating Tank
A completely filled cylindrical tank of water rotates at . Determine the pressure increase from the rotation axis to radius at the same elevation.
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0 of 2 Steps CompletedGage Pressure at a Point in an Open Forced Vortex
Take the free-surface vertex of a rotating open water tank as , , with positive upward. At a point and , the liquid rotates at . Determine gage pressure.
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0 of 2 Steps CompletedSpilled Volume from a Rotating Cylindrical Tank
A cylindrical tank has radius , height , and initial water depth . After rotation and spillage reach relative equilibrium, the free surface is at the rim at the wall and the center-to-wall elevation difference is . The center remains wetted. Determine the spilled volume.