MCQOPTIONS
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MCQOPTIONS
This section includes 88 Mcqs, each offering curated multiple-choice questions to sharpen your Fluid Mechanics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A fluid is defined as one which: |
| A. | is solid-like when there is no motion |
| B. | deforms continuously when subjected to shear stress |
| C. | cannot withstand shear |
| D. | can withstand elongation |
| Answer» C. cannot withstand shear | |
| 2. |
Consider the following properties:1. Energy5. Pressure2. Entropy6. Temperature3. Gibbs energy7. Viscosity4. Volume8. ElasticityWhich of the above are intensive properties? |
| A. | 1, 3, 5, 6 |
| B. | 5, 6, 7, 8 |
| C. | 1, 3, 5, 6, 7, 8 |
| D. | 4, 5, 6 8 |
| Answer» C. 1, 3, 5, 6, 7, 8 | |
| 3. |
Kinematic viscosity is expressed in |
| A. | stoke |
| B. | m2/sec |
| C. | cm2/sec |
| D. | all of the above |
| Answer» E. | |
| 4. |
Milk mixes with water due to |
| A. | Very good cohesion |
| B. | Very good adhesion |
| C. | Very good surface tension |
| D. | Very good vapour pressure |
| Answer» C. Very good surface tension | |
| 5. |
Fluids undergo volume change under external pressure due to |
| A. | Plasticity |
| B. | Viscosity |
| C. | Tenacity |
| D. | Compressibility |
| Answer» E. | |
| 6. |
Choose the best option for the Newtonian fluid |
| A. | Frictionless and incompressible |
| B. | Viscosity is invariant with shear stress |
| C. | Viscosity decreases at higher shear stress |
| D. | Viscosity increases at higher shear stress |
| Answer» C. Viscosity decreases at higher shear stress | |
| 7. |
How many poise is one pascal second? |
| A. | 12 |
| B. | 13 |
| C. | 14 |
| D. | 10 |
| Answer» E. | |
| 8. |
A plate 0.025 mm distant from a fixed plate moves at 60 cm/s and requires a force of 0.2 kgf/m2 to maintain this speed. The dynamic viscosity of the fluid between the plates will be nearly |
| A. | 9.2 × 10-10kgfs/cm2 |
| B. | 8.3 × 10-10kgfs/cm2 |
| C. | 7.4 × 10-10kgfs/cm2 |
| D. | 6.5 × 10-10kgfs/cm2 |
| Answer» C. 7.4 × 10-10kgfs/cm2 | |
| 9. |
Mercury is considered as a superior barometric fluid chiefly due to its |
| A. | Negligible small vapour pressure |
| B. | High specific heat |
| C. | High specific gravity |
| D. | Convex meniscus |
| Answer» B. High specific heat | |
| 10. |
An odd shaped body weighing 7.5 kg and occupying 0.01 cubic metre volume will be completely submerged in a fluid having specific gravity of _____. |
| A. | 1 |
| B. | 1.2 |
| C. | 0.8 |
| D. | 0.75 |
| Answer» E. | |
| 11. |
Find the surface tension in soap bubble of 40 mm diameter when the inside pressure is 2.5 N/m2 above atmospheric pressure. |
| A. | 0.0064 N/m |
| B. | 0.860 N/m |
| C. | 1.265 N/m |
| D. | 0.0125 N/m |
| Answer» E. | |
| 12. |
A real fluid in which the shear stress is proportional to the rate of shear strain is known as _______. |
| A. | Real fluid |
| B. | Newtonian fluid |
| C. | Ideal plastic fluid |
| D. | Compressed fluid |
| Answer» C. Ideal plastic fluid | |
| 13. |
In the context of fluid mechanics. which of the following statements is INCORRECT? |
| A. | Fluid continues in motion under the application of shear stress. |
| B. | Fluid does not deform continuously under shear stress. |
| C. | Fluid cannot sustain any shear stress when at rest. |
| D. | Fluid deforms under very small shear stress. |
| Answer» C. Fluid cannot sustain any shear stress when at rest. | |
| 14. |
In which of the following units is the kinematic viscosity of a fluid expressed? |
| A. | N/m2.s |
| B. | N.s/m2 |
| C. | m2/s |
| D. | N.s/m |
| Answer» D. N.s/m | |
| 15. |
A small pressure difference between two points along a pipeline carrying water is to be measured using a U-tube manometer. The manometric fluid to be used is: |
| A. | Mercury |
| B. | Carbon tetrachloride |
| C. | Water |
| D. | Kerosene |
| Answer» C. Water | |
| 16. |
Falling drops of water become spheres due to the property of _______. |
| A. | Adhesion |
| B. | Cohesion |
| C. | Surface tension |
| D. | Viscosity |
| Answer» D. Viscosity | |
| 17. |
Find the mass of the part shown in figure, ρ = 10 gm/cm3 (π = 22/7).Note: All dimensions are in mm |
| A. | 221 gm |
| B. | 925 gm |
| C. | 52900 gm |
| D. | 529 gm |
| Answer» E. | |
| 18. |
\(\nu = 0.0022t - \frac{{1.8}}{t}\) is the equation to determine kinematic viscosity of liquids by |
| A. | Redwood Viscometer |
| B. | Engler Viscometer |
| C. | Saybolt universal viscometer |
| D. | Newton Viscometer |
| Answer» D. Newton Viscometer | |
| 19. |
Poise is a unit of |
| A. | Surface tension |
| B. | Viscosity |
| C. | Capillarity |
| D. | Shear stress in fluids |
| Answer» C. Capillarity | |
| 20. |
In a static fluid, _______. |
| A. | linear deformation is small |
| B. | Resistance to shear stress is small |
| C. | Only normal stress can exist |
| D. | Fluid pressure is small |
| Answer» D. Fluid pressure is small | |
| 21. |
A unidirectional fibre-epoxy composite contains 65% by volume fibre and 35% epoxy resin. If the relative density of the fibre is 1.48 and of the resin is 1.2, the percentage weight of fibre will be nearly |
| A. | 70% |
| B. | 75% |
| C. | 80% |
| D. | 85% |
| Answer» B. 75% | |
| 22. |
A plate 0.02 mm distant from a fixed plate moves at 20 cm/s requires a shear stress of 4 N/m2 to maintain this speed. Viscosity of fluid available inside these plates is: |
| A. | 4 × 10-4 poise |
| B. | 4 × 10-6 poise |
| C. | \(4 \times {10^{ - 5}}\frac{{Ns}}{{{m^2}}}\) |
| D. | \(4 \times {10^{ - 4}}\frac{{Ns}}{{{m^2}}}\) |
| Answer» E. | |
| 23. |
In the isothermal condition, the isothermal bulk modulus of an ideal gas is equal to ______. |
| A. | constant |
| B. | pressure |
| C. | temperature |
| D. | viscosity |
| Answer» C. temperature | |
| 24. |
In the given figure, which nature of fluid is represented by curve A? |
| A. | Newtonian |
| B. | Pseudo-plastic |
| C. | Dilatant |
| D. | Ideal Bingham plastic |
| Answer» E. | |
| 25. |
A fluid which has shear stress is proportional to the rate of shear strain is called: |
| A. | Real fluid |
| B. | Ideal plastic fluid |
| C. | Ideal fluid |
| D. | Non Newtonian fluid |
| Answer» B. Ideal plastic fluid | |
| 26. |
If the relationship between shear stress of a fluid is NOT linear to the velocity gradient, then the fluid is: |
| A. | a compressible fluid |
| B. | a non-Newtonian fluid |
| C. | an ideal fluid |
| D. | a Newtonian fluid |
| Answer» C. an ideal fluid | |
| 27. |
A small capillary tube of 3 mm inner diameter is inserted into a fluid having density 900 kg/m3 , surface tension 0.1 N/m, and contact angle 30°. The rise in the height of fluid in the capillary tube due to surface tension is |
| A. | 111.4 mm |
| B. | 13.078 mm |
| C. | 89.1 mm |
| D. | 154.1 mm |
| Answer» C. 89.1 mm | |
| 28. |
Fluids change the volume under external pressure due to: |
| A. | Plasticity |
| B. | Elasticity |
| C. | Viscosity |
| D. | Compressibility |
| Answer» E. | |
| 29. |
Pascal second is the unit of |
| A. | Pressure |
| B. | Kinematic viscosity |
| C. | Dynamic viscosity |
| D. | Surface tension |
| Answer» D. Surface tension | |
| 30. |
A solid sphere of radius, r, and made of material with density ρs, is moving through the atmosphere (constant pressure, p) with a velocity, v. The net force ONLY due to atmospheric pressure (Fp) acting on the sphere at any time, t, is |
| A. | \(\frac{4}{3}\pi {r^3}{\rho _s}\frac{{dv}}{{dt}}\) |
| B. | zero |
| C. | πr2p |
| D. | 4π2p |
| Answer» C. πr2p | |
| 31. |
Mercury is a suitable fluid for a barometer because it: |
| A. | Has very low vapour pressure at room temperature |
| B. | Wets the glass surface |
| C. | Has a low boiling point |
| D. | Has high vapour pressure at room temperature |
| Answer» B. Wets the glass surface | |
| 32. |
If the surface tension of a soap air interface is 0.09 N/m, the difference between the internal and external pressure in the sap bubble of 3 cm diameter is |
| A. | 22 |
| B. | 20 |
| C. | 24 |
| D. | 30 |
| E. | 36 |
| Answer» D. 30 | |
| 33. |
A real fluid in which the shear stress is directly proportional to the rate of shear strain is known as: |
| A. | ideal plastic fluid |
| B. | ideal fluid |
| C. | non-Newtonian fluid |
| D. | Newtonian fluid |
| E. | non-ideal fluid |
| Answer» E. non-ideal fluid | |
| 34. |
A fluid which is incompressible and has no viscosity is known as a/an: |
| A. | Newtonian fluid |
| B. | non-Newtonian fluid |
| C. | ideal fluid |
| D. | ideal plastic fluid |
| E. | real fluid |
| Answer» D. ideal plastic fluid | |
| 35. |
Paper pulp can be regarded as |
| A. | Bingham plastic fluid |
| B. | Dilatant fluid |
| C. | Newtonian fluid |
| D. | Pseudo plastic fluid |
| Answer» E. | |
| 36. |
In CGS system, the unit of kinematic viscosity is stoke, where 1 stoke =_____. |
| A. | 106 cm3/s |
| B. | 10-2 m2 |
| C. | 104 cm3/s |
| D. | 10-4 m2/s |
| Answer» E. | |
| 37. |
In an ideal fluid flow, the: |
| A. | surface tension forces are zero. |
| B. | pressure is equal everywhere. |
| C. | Viscosity is zero. |
| D. | pressure increases linearly with depth |
| Answer» D. pressure increases linearly with depth | |
| 38. |
_______ is the unit of relative density. |
| A. | gm/cc |
| B. | m/s |
| C. | kg/cm2 |
| D. | None of these |
| Answer» E. | |
| 39. |
If the density of a liquid is 50 kg/m3, then specific volume of liquid is |
| A. | 0.02 m3/kg |
| B. | 0.05 m3/kg |
| C. | 400 m3/kg |
| D. | 500 m3/kg |
| Answer» B. 0.05 m3/kg | |
| 40. |
The viscosity as a property of fluid indicates: |
| A. | Variation of static pressure with height in the liquid body |
| B. | How well the fluid will adhere to a metal surface |
| C. | Its resistance to flow over the surface |
| D. | Variation of thermal conductivity with temperature |
| Answer» D. Variation of thermal conductivity with temperature | |
| 41. |
A fan supplies 250 CFM air flow rate. It is equal to____m3/s. |
| A. | 0.095 |
| B. | 0.118 |
| C. | 0.127 |
| D. | 0.175 |
| Answer» C. 0.127 | |
| 42. |
Flow of air can be considered to be incompressible within 1% error if the mach number of flow is less than _____. |
| A. | 0.4 |
| B. | 0.6 |
| C. | 0.1 |
| D. | 0.3 |
| Answer» E. | |
| 43. |
Pressure intensity inside the soap bubble is(where σ = Surface tension, d = diameter of bubble) |
| A. | P = 8σ/d |
| B. | P = 2σ/d |
| C. | P = 4σ/d |
| D. | P = σ/d |
| Answer» B. P = 2σ/d | |
| 44. |
If pressure at any point in the liquid approaches the vapor pressure, liquid starts vaporising and creates pockets or bubbles of dissolved gases and vapours. This phenomenon is ________. |
| A. | Surface tension |
| B. | Adhesion |
| C. | Vaporisation |
| D. | Cavitation |
| Answer» E. | |
| 45. |
A fluid, in which shear stress is more than the yield value and shear stress is proportional to the rate of shear strain is known as: |
| A. | Newtonian fluid |
| B. | Ideal Plastic Fluid |
| C. | Real Fluid |
| D. | Ideal fluid |
| Answer» C. Real Fluid | |
| 46. |
If one liter of a fluid has a mass of 7.5 kg then its specific gravity is: |
| A. | 0.75 |
| B. | 7.5 |
| C. | 75 |
| D. | 750 |
| Answer» C. 75 | |
| 47. |
Property of a fluid by which molecules of different kinds of fluids are attracted to each other is called _____. |
| A. | Adhesion |
| B. | Cohesion |
| C. | Viscosity |
| D. | Compressibility |
| Answer» B. Cohesion | |
| 48. |
Dynamic viscosity has the dimensions as |
| A. | MLT-1 |
| B. | ML-1T-1 |
| C. | ML-1T-2 |
| D. | M-1L-1T-1 |
| Answer» C. ML-1T-2 | |
| 49. |
In the CGS unit, dynamic viscosity is expressed as |
| A. | poise |
| B. | Pa-s |
| C. | stokes |
| D. | None of the above |
| Answer» B. Pa-s | |
| 50. |
Density of an ideal fluid is always _____ |
| A. | constant |
| B. | zero |
| C. | decreasing |
| D. | increasing |
| Answer» B. zero | |