Mechanical Operations interview questions

1. A.surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
2. B.energy for size reduction is proportional to the new surface area created, which fits fine grinding best
3. C.superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended
4. D.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity

Answer + AI explanation with Pro

1. A.Minimum fluidisation velocity
2. B.Thickener area (Coe-Clevenger)
3. C.Rittinger's law
4. D.Kick's law

Answer + AI explanation with Pro

1. A.Rittinger's law — surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
2. B.Rittinger's law — energy for size reduction is proportional to the new surface area created, which fits fine grinding best
3. C.Rittinger's law — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
4. D.Rittinger's law — energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best

Answer + AI explanation with Pro

1. A.energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
2. B.energy for size reduction is proportional to the new surface area created, which fits fine grinding best
3. C.dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
4. D.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity

Answer + AI explanation with Pro

1. A.Kick's law
2. B.Rittinger's law
3. C.Minimum fluidisation velocity
4. D.Stokes' law

Answer + AI explanation with Pro

1. A.Kick's law — terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
2. B.Kick's law — surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
3. C.Kick's law — energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
4. D.Kick's law — superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended

Answer + AI explanation with Pro

1. A.energy for size reduction is proportional to the new surface area created, which fits fine grinding best
2. B.surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
3. C.dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
4. D.energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm

Answer + AI explanation with Pro

1. A.Thickener area (Coe-Clevenger)
2. B.Bond's law
3. C.Rittinger's law
4. D.Stokes' law

Answer + AI explanation with Pro

1. A.Bond's law — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
2. B.Bond's law — superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended
3. C.Bond's law — filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
4. D.Bond's law — energy for size reduction is proportional to the new surface area created, which fits fine grinding best

Answer + AI explanation with Pro

1. A.surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
2. B.energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
3. C.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
4. D.required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations

Answer + AI explanation with Pro

1. A.Kick's law
2. B.Minimum fluidisation velocity
3. C.Thickener area (Coe-Clevenger)
4. D.Stokes' law

Answer + AI explanation with Pro

1. A.Stokes' law — terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
2. B.Stokes' law — dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
3. C.Stokes' law — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
4. D.Stokes' law — required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations

Answer + AI explanation with Pro

1. A.filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
2. B.energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
3. C.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
4. D.surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation

Answer + AI explanation with Pro

1. A.Constant-pressure filtration
2. B.Sphericity
3. C.Thickener area (Coe-Clevenger)
4. D.Stokes' law

Answer + AI explanation with Pro

1. A.Constant-pressure filtration — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
2. B.Constant-pressure filtration — dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
3. C.Constant-pressure filtration — energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
4. D.Constant-pressure filtration — filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept

Answer + AI explanation with Pro

1. A.energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best
2. B.energy for size reduction is proportional to the new surface area created, which fits fine grinding best
3. C.superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended
4. D.filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept

Answer + AI explanation with Pro

1. A.Minimum fluidisation velocity
2. B.Power number
3. C.Kick's law
4. D.Rittinger's law

Answer + AI explanation with Pro

1. A.Minimum fluidisation velocity — terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
2. B.Minimum fluidisation velocity — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
3. C.Minimum fluidisation velocity — superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended
4. D.Minimum fluidisation velocity — dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks

Answer + AI explanation with Pro

1. A.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity
2. B.surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
3. C.filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
4. D.dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks

Answer + AI explanation with Pro

1. A.Thickener area (Coe-Clevenger)
2. B.Minimum fluidisation velocity
3. C.Sphericity
4. D.Rittinger's law

Answer + AI explanation with Pro

1. A.Sphericity — energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
2. B.Sphericity — surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation
3. C.Sphericity — filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
4. D.Sphericity — energy for size reduction is proportional to the logarithm of the feed-to-product size ratio, which fits coarse crushing best

Answer + AI explanation with Pro

1. A.superficial gas velocity at which bed pressure drop equals bed weight per unit area and the particles just become suspended
2. B.dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
3. C.filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
4. D.required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations

Answer + AI explanation with Pro

1. A.Thickener area (Coe-Clevenger)
2. B.Bond's law
3. C.Power number
4. D.Rittinger's law

Answer + AI explanation with Pro

1. A.Power number — dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
2. B.Power number — required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations
3. C.Power number — energy for size reduction is proportional to the new surface area created, which fits fine grinding best
4. D.Power number — surface area of a sphere of equal volume divided by the actual particle surface area, equal to 1 for spheres and used in the Ergun equation

Answer + AI explanation with Pro

1. A.required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations
2. B.energy is proportional to the difference of reciprocal square roots of product and feed sizes; the work index is kWh per tonne from infinite size to 100 μm
3. C.dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
4. D.terminal settling velocity of a small sphere in laminar flow is proportional to diameter squared and density difference divided by 18 times viscosity

Answer + AI explanation with Pro

1. A.Minimum fluidisation velocity
2. B.Stokes' law
3. C.Power number
4. D.Thickener area (Coe-Clevenger)

Answer + AI explanation with Pro

1. A.Thickener area (Coe-Clevenger) — dimensionless agitator power P/(ρN³D⁵), which becomes constant at high impeller Reynolds number in fully baffled tanks
2. B.Thickener area (Coe-Clevenger) — energy for size reduction is proportional to the new surface area created, which fits fine grinding best
3. C.Thickener area (Coe-Clevenger) — filtrate volume squared grows linearly with time; a plot of t/V against V gives cake and medium resistances from slope and intercept
4. D.Thickener area (Coe-Clevenger) — required settling area is set by the concentration zone with the lowest solids flux, found from batch settling tests at several concentrations

Answer + AI explanation with Pro