MCQOPTIONS
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MCQOPTIONS
This section includes 659 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 651. |
A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, then the new head will be ______________ metres? |
| A. | 2 |
| B. | 4 |
| C. | 8 |
| D. | 5.5 |
| Answer» B. 4 | |
| 652. |
A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump_________________? |
| A. | Develops a lower head |
| B. | Capacity is reduced |
| C. | Requires more power |
| D. | All A., B. and C. |
| Answer» E. | |
| 653. |
A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, the new discharge will be __________ litres/minute ? |
| A. | 500 |
| B. | 200 |
| C. | 1000 |
| D. | 750 |
| Answer» B. 200 | |
| 654. |
A Bingham fluid of viscosity μ = 10 Pa.s and yield stress, η0 = 10 KPa, is shared between flat parallel plates separated by a distance of 10-3 m. The top plate is moving with a velocity of 1 m/s. The shear stress on the plate is________________? |
| A. | 10 KPa |
| B. | 20 KPa |
| C. | 30 KPa |
| D. | 40 KPa |
| Answer» C. 30 KPa | |
| 655. |
A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun’s equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 × 103 VOM + 10.94 × 106 V2 OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is_________________? |
| A. | 12 mm/s |
| B. | 16 mm/s |
| C. | 24 mm/s |
| D. | 28 mm/s |
| Answer» C. 24 mm/s | |
| 656. |
A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun’s equation for the above fluid-particle system (in SI units) is given below: Δ P/L = 375 × 103 VOM + 10.94 × 106 V2 OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed ? |
| A. | 0.2 |
| B. | 0.5 |
| C. | 0.7 |
| D. | 0.8 |
| Answer» D. 0.8 | |
| 657. |
A bed consists of particles of density 2000 kg/m3. If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is_________________? |
| A. | 25.61 kPa |
| B. | 11.77 kPa |
| C. | 14.86 kPa |
| D. | 21.13 kPa |
| Answer» C. 14.86 kPa | |
| 658. |
A 2″ gate valve fitted in a pipe is replaced by a similar globe valve. Pressure drop in gate valve was Δp. For the same discharge, the pressure drop across globe valve is__________________? |
| A. | Δp |
| B. | < Δp |
| C. | > Δp |
| D. | Δp2 |
| Answer» D. Δp2 | |
| 659. |
A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is________________? |
| A. | 4.4 KPa |
| B. | 2.94 KPa |
| C. | 3.7 KPa |
| D. | None of these |
| Answer» B. 2.94 KPa | |