MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 2158 Mcqs, each offering curated multiple-choice questions to sharpen your GATE (Mechanical Engineering) knowledge and support exam preparation. Choose a topic below to get started.
| 901. |
Efficiency of power transmission (η) through a circular pipe is given by (ht - hf)/ht, which has a maximum value of __________ percent. |
| A. | 33:3 |
| B. | 50 |
| C. | 66.6 |
| D. | 88.8 |
| Answer» D. 88.8 | |
| 902. |
Bernoulli's equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli's equation ?A. Fluid flow is frictionless & irrotational. B. Fluid flow is steady. C. Fluid flow is uniform & turbulent.D. Fluid is compressible.E. Fluid is incompressible. |
| A. | A, C, D |
| B. | B, D, E |
| C. | A, B, E |
| D. | A, D, E |
| Answer» D. A, D, E | |
| 903. |
Which of the following valves will incur maximum pressure drop for the same discharge of water ? |
| A. | Globe valve |
| B. | Gate valve |
| C. | Needle valve |
| D. | Butterfly valve |
| Answer» D. Butterfly valve | |
| 904. |
Which of the following can be used for the direct measurement of volumetric flow rate of slurry ? |
| A. | Venturimeter |
| B. | Orificemeter |
| C. | Rotameter |
| D. | Pitot tube |
| Answer» D. Pitot tube | |
| 905. |
Which of the following fluid forces are not considered in the Navier-Stoke's equation? |
| A. | Gravity forces |
| B. | Viscous forces |
| C. | Pressure forces |
| D. | Turbulent forces |
| Answer» E. | |
| 906. |
Which of the following properties of a fluid is responsible for offering resistance to shear ? |
| A. | Surface tension. |
| B. | Viscosity. |
| C. | Specific gravity. |
| D. | All (a), (b), and (c). |
| Answer» C. Specific gravity. | |
| 907. |
In which of the following body shapes, the pressure drag is large compared to the friction drag ? |
| A. | Stream line body |
| B. | Two dimensional body |
| C. | Bluff body |
| D. | None of these |
| Answer» D. None of these | |
| 908. |
Stoke's law is valid, when Nʀₑ, p is less than |
| A. | 2 |
| B. | 100 |
| C. | 2100 |
| D. | 700 |
| Answer» B. 100 | |
| 909. |
Which of the following has the minimum compressibility ? |
| A. | Water at room temperature |
| B. | Air at room temperature |
| C. | Oxygen at room temperature |
| D. | Nitrogen at room temperature |
| Answer» B. Air at room temperature | |
| 910. |
As the velocity V and thus the Reynolds number of a flow past a sphere increases from very low value, the drag force for Re |
| A. | increases linearly with V. |
| B. | decreases linearly with V. |
| C. | decreases as V². |
| D. | none of these. |
| Answer» B. decreases linearly with V. | |
| 911. |
A fluid (μ/ρ = 0.01 cm²/sec) is moving at critical flow condition (Nʀₑ = 2100) through a pipe of dia 3 cms. Velocity of flow is __________ cm/sec. |
| A. | 7 |
| B. | 700 |
| C. | 7000 |
| D. | 630 |
| Answer» B. 700 | |
| 912. |
Out of the following flow measuring devices, which one incurs the maximum installation cost as well as pressure loss ? |
| A. | Flow nozzle |
| B. | Venturimeter |
| C. | Rotameter |
| D. | Orificemeter |
| Answer» C. Rotameter | |
| 913. |
At what value of crank angle (roughly), no flow of water from or into the air vessel takes place in case of a double acting reciprocating pump ? |
| A. | 40° and 140° |
| B. | 45° and 60° |
| C. | 90° and 80° |
| D. | 20° and 120° |
| Answer» B. 45° and 60° | |
| 914. |
What is the shear rate at the pipe wall, in case of laminar flow of Newtonion fluids in a pipe of diameter 'D' & length 'L' incurring a pressure drop 'Δp' with average velocity 'Vₐᵥ'? |
| A. | D Δp/8L |
| B. | D Δp/4L |
| C. | 8 . Vₐᵥ/D |
| D. | 4 . Vₐᵥ/D |
| Answer» D. 4 . Vₐᵥ/D | |
| 915. |
A spherical particle is falling slow in a viscous liquid such that Reynolds number is less than 1. Which statement is correct for this situation ? |
| A. | Inertial and drag forces are important. |
| B. | Drag, gravitational and buoyancy forces are impportant. |
| C. | Drag force and gravitational forces are important. |
| D. | None of the above. |
| Answer» C. Drag force and gravitational forces are important. | |
| 916. |
A gas (density = 1.5 kg/m³ , viscosity = 2x 10⁻⁵ kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m³and viscosity of 3 x 10⁻⁵ kg/m.s flowing at 3 m/s will be |
| A. | 8400 Pa/m |
| B. | 12600 Pa/m |
| C. | 18900 Pa/m |
| D. | 16800 Pa/m |
| Answer» C. 18900 Pa/m | |
| 917. |
Which of the following conditions must be satisfied for lift force to be developed ? |
| A. | The body should be bluff body. |
| B. | The body should be stream lined. |
| C. | Circulation around the body is essentially required. |
| D. | The main stream velocity must approach the velocity of sound in that fluid medium. |
| Answer» D. The main stream velocity must approach the velocity of sound in that fluid medium. | |
| 918. |
Which of the following quantities are computed by using the hydraulic radius for non-circular ducts ? |
| A. | Velocity and relative roughness. |
| B. | Head loss and velocity. |
| C. | Reynold number, relative roughness and head loss. |
| D. | Reynolds number and friction factor. |
| Answer» D. Reynolds number and friction factor. | |
| 919. |
In which of the following cases, it is possible for flow to occur from low pressure to high pressure ? |
| A. | Flow of liquid upward in a vertical pipe. |
| B. | Flow through a converging section. |
| C. | Flow of air downward in a pipe. |
| D. | Impossible in a constant cross-section conduit. |
| Answer» C. Flow of air downward in a pipe. | |
| 920. |
At a constant speed of the centrifugal pump, its __________ the impeller diameter. |
| A. | capacity varies directly with |
| B. | head varies as the square of |
| C. | horsepower varies as the cube of |
| D. | all (a), (b) and (c) |
| Answer» E. | |
| 921. |
Which of the following two quantities when same, makes one pipe system equivalent to another pipe system ? |
| A. | Head & discharge |
| B. | Length & discharge |
| C. | Length & diameter |
| D. | Friction factor & diameter. |
| Answer» B. Length & discharge | |
| 922. |
An ideal plastic substance indicates no deformation, when stressed upto yield stress, but behaves like a Newtonion fluid beyond yield stress. Which of the following is an ideal plastic ? |
| A. | Sewage sludge |
| B. | Rubber latex |
| C. | Blood |
| D. | Sugar solution |
| Answer» B. Rubber latex | |
| 923. |
N. second/m² is |
| A. | the S.I. unit of dynamic viscosity. |
| B. | the S.I. unit of kinematic viscosity. |
| C. | equivalent to one poise. |
| D. | equivalent to one stoke. |
| Answer» B. the S.I. unit of kinematic viscosity. | |
| 924. |
What is the value of co-efficient of discharge for square edged circular orifice (for β = 0.3 to 0.5) ? |
| A. | 0.61 - 0.63 |
| B. | 0.5 - 0.75 |
| C. | 0.75 - 0.90 |
| D. | 0.35 - 0.55 |
| Answer» B. 0.5 - 0.75 | |
| 925. |
A centrifugal pump has the following specifications: Power = 4 H.P.Speed = 800 rpmHead = 8 metresFlow = 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 | |
| 926. |
What is the unit of kinematic viscosity in SI unit ? |
| A. | m²/sec |
| B. | N/m² . sec |
| C. | Kg . sec/m |
| D. | None of these |
| Answer» B. N/m² . sec | |
| 927. |
Cd for the orifice plate varies from |
| A. | 0.58 to 0.8 |
| B. | 0.93 to 0.98 |
| C. | 0.2 to 0.3 |
| D. | 0.02 to 0.03 |
| Answer» B. 0.93 to 0.98 | |
| 928. |
What type of motion the fluid element undergoes, when it changes from one position to another position, such that the angle between the two sides change ? |
| A. | Rotation |
| B. | Translation |
| C. | Linear deformation |
| D. | Angular deformation |
| Answer» E. | |
| 929. |
The hydraulic diameter of an annulus of inner and outer radii Rᵢ and R₀ respectively is |
| A. | 4(R₀-Rᵢ) |
| B. | √(R₀-Rᵢ) |
| C. | 2(R₀-Rᵢ) |
| D. | R₀ + Rᵢ |
| Answer» D. R₀ + Rᵢ | |
| 930. |
Which of the following equations applies to the fluid flow through a packed bed for very large Reynolds number ? |
| A. | Fanning equation |
| B. | Blake-Pllummer equation |
| C. | Hagen-Poiseulle equation |
| D. | Kozney-Karman equation |
| Answer» C. Hagen-Poiseulle equation | |
| 931. |
Rubber latex is an example of a __________ fluid. |
| A. | pseudoplastic |
| B. | bingham plastic |
| C. | dilatent |
| D. | Newtonion |
| Answer» B. bingham plastic | |
| 932. |
Enamels and paints are generally __________ fluid. |
| A. | reheopectic |
| B. | pseudo-plastic |
| C. | thixotropic |
| D. | dilatant |
| Answer» C. thixotropic | |
| 933. |
Cavitation in a pump creates so many undesirable effects. Out of the following, which is not an undesirable effect created by cavitation ? |
| A. | Decrease in effect |
| B. | Increase in thrust |
| C. | Develops noise |
| D. | Develops high pressure |
| Answer» E. | |
| 934. |
For a particle settling in water at its terminal settling velocity, which of the following is true ? |
| A. | Buoyancy = weight + drag |
| B. | Weight = buoyancy + drag |
| C. | Drag = buoyancy + weight |
| D. | Drag = weight |
| Answer» C. Drag = buoyancy + weight | |
| 935. |
What is the value of Fanning friction factor ' f ' for smooth pipe at Nʀₑ = 10⁶ approximately ? |
| A. | 0.003 |
| B. | 0.01 |
| C. | 0.1 |
| D. | 0.3 |
| Answer» B. 0.01 | |
| 936. |
Which of the following is used for pumping crude oil from oil well ? |
| A. | Single stage centrifugal pump |
| B. | Gear pump |
| C. | Screw pump |
| D. | Duplex/triplex reciprocating pump |
| Answer» E. | |
| 937. |
Which of the following produces maximum pressure difference for transportation of gases ? |
| A. | Vaccum pumps |
| B. | Blowers |
| C. | Fans |
| D. | Compressors |
| Answer» E. | |
| 938. |
What is the maximum theoretical suction lift (metres) of a reciprocating pump ? |
| A. | 5 |
| B. | 10 |
| C. | 50 |
| D. | 100 |
| Answer» C. 50 | |
| 939. |
What is the pipe called which lifts water from a reservoir to a greater height than the initial level in the supply reservoir ? |
| A. | Penstock |
| B. | Siphon |
| C. | Tunnel |
| D. | Pressure pipeline |
| Answer» C. Tunnel | |
| 940. |
Which law/principle of solid mechanics is similar/equivalent to Newton's law of viscosity in fluid mechanics ? |
| A. | Archimedes principle. |
| B. | Newton's second law of motion. |
| C. | Hooke's law. |
| D. | Newton's third law of motion. |
| Answer» D. Newton's third law of motion. | |
| 941. |
For Laminar flow through a packed bed, the pressure drop is proportional to (Vₛ is the superficial liquid velocity and Dₚ is the particle diameter) |
| A. | Vₛ/Dₚ² |
| B. | Vₛ²/Dₚ² |
| C. | Vₛ²/Dₚ³ |
| D. | Vₛ/Dₚ³ |
| Answer» B. Vₛ²/Dₚ² | |
| 942. |
Friction factor for a hydraulically smooth pipe at Nʀₑ = 2100 is f₁. If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of Nʀₑ, will |
| A. | increase. |
| B. | decrease. |
| C. | remain unchanged. |
| D. | increase or decrease depending on the pipe material. |
| Answer» B. decrease. | |
| 943. |
Centrifugal pumps as compared to reciprocating pumps |
| A. | run at a lower speed for the same discharge. |
| B. | do not need priming. |
| C. | deliver fluid with pulsating/fluctuating discharge. |
| D. | can be run with discharge line valve closed for a short interval. |
| Answer» E. | |
| 944. |
Which of the following equations as suggested by Colebrook and White gives the increase in roughness of a new surface (ε₀) with age/time (t) (where, ε = roughness of the surface after time't'. α = a co-efficient to be experimentally determined)? |
| A. | ε = ε₀ + α.t |
| B. | ε = ε₀ + α.t² |
| C. | ε = ε₀ + α.t³ |
| D. | ε = ε₀ + α.t⁴ |
| Answer» B. ε = ε₀ + α.t² | |
| 945. |
Which of the following is used for very accurate measurement of flow of gas at low velocity ? |
| A. | Pitot tube |
| B. | Rotameter |
| C. | Segmental orificemeter |
| D. | Hot wire annemometer |
| Answer» E. | |
| 946. |
Which of the following has the maximum compression ratio ? |
| A. | Blower |
| B. | Compressor |
| C. | Vacuum pump |
| D. | Fan |
| Answer» D. Fan | |
| 947. |
Umf is the minimum fluidisation velocity for a bed of particles. An increase in the superficial gas velocity from 2 Umf to 2.5 Umf results in (all velocities are smaller than the entrainment velocity of the particles) no change in the |
| A. | drag on particles |
| B. | drag on coloumn walls |
| C. | bed height |
| D. | bed voidage |
| Answer» D. bed voidage | |
| 948. |
The fluid velocity varies as the square root of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop for __________ fluid. |
| A. | dilatant |
| B. | pseudoplastic |
| C. | Bingham plastic |
| D. | Newtonion |
| Answer» B. pseudoplastic | |
| 949. |
What is the ratio of displacement thickness to nominal thickness for a linear distribution of velocity in the boundary layer on a flat plate ? |
| A. | 0.5 |
| B. | 1 |
| C. | 1.5 |
| D. | 2 |
| Answer» B. 1 | |
| 950. |
In case of isentropic flow, the speed of sound in an ideal gas is proportional to (where, T = absolute temperature ) |
| A. | 1/√T |
| B. | 1/T |
| C. | √T |
| D. | T |
| Answer» D. T | |