MCQOPTIONS
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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.
| 101. |
The laminar flow is characterized by |
| A. | Existence of eddies |
| B. | Irregular motion of fluid particles |
| C. | Fluid particles moving in layers parallel to the boundary surface |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 102. |
In case of a laminar flow, the loss of pressure head is |
| A. | Proportional to (velocity)2 |
| B. | Proportional to velocity |
| C. | Proportional to (velocity)1/2 |
| D. | None of the above. |
| Answer» C. Proportional to (velocity)1/2 | |
| 103. |
Velocity head is given by |
| A. | V/g |
| B. | V2/2g |
| C. | V3/2g |
| D. | V2/2g2 |
| Answer» C. V3/2g | |
| 104. |
Which of the following is an example of free vortex flow? |
| A. | A whirlpool in a river |
| B. | Flow of liquid through a hole provided at the bottom of a container |
| C. | Flow of liquid around a circular bend in a pipe. |
| D. | All of the above. |
| Answer» E. | |
| 105. |
......... is the ratio of the inertia force to the viscous force. |
| A. | Froude’s number |
| B. | Weber’s number |
| C. | Reynolds number |
| D. | Mach’s number. |
| Answer» D. Mach’s number. | |
| 106. |
...... is equal to the product of shear stress due to viscosity and surface area of flow. |
| A. | Viscous force |
| B. | Inertia force |
| C. | Pressure force |
| D. | Gravity force. |
| Answer» B. Inertia force | |
| 107. |
Which of the following statements is correct: Runaway speed of a hydraulic turbine is the speed |
| A. | At which there would be no damage to the turbine runner |
| B. | At which the turbine runner can be allowed to run freely without load and with wicket gates wide open |
| C. | Corresponding to maximum overload permissible |
| D. | At full load. |
| Answer» C. Corresponding to maximum overload permissible | |
| 108. |
The fundamental S.I. unit of pressure is N/m2; this is also known as ...... |
| A. | Pascal |
| B. | Stoke |
| C. | Poise |
| D. | None of the above |
| Answer» B. Stoke | |
| 109. |
A....is an imaginary line within the flow so that the tangent at any point on it indicates the velocity at thatpoint. |
| A. | Streak line |
| B. | Stream line |
| C. | Path line |
| D. | None of the above. |
| Answer» C. Path line | |
| 110. |
The entrance length or length of establishment of flow is |
| A. | The length in which the boundary layer remains uniform |
| B. | The pipe length inside the reservoir |
| C. | The length of pipe from its entrance in which the flow may be assumed irrotational |
| D. | The initial length in which the flow develops fully such that the velocity profile does not change downstream. |
| Answer» E. | |
| 111. |
When a steady jet impinges on a fixed inclined surface |
| A. | The flow is divided into parts proportional to the angle of inclination of the surface |
| B. | No force is exerted by the jet on the vane |
| C. | The momentum component is unchanged parallel to the surface |
| D. | None of the above. |
| Answer» B. No force is exerted by the jet on the vane | |
| 112. |
Lock gates are provided to |
| A. | Change the water level in a canal or river for irrigation |
| B. | Store water for irrigation purpose |
| C. | Either of the above |
| D. | None of the above. |
| Answer» B. Store water for irrigation purpose | |
| 113. |
The flow in a river during the period of heavy rainfall is |
| A. | Steady, non-uniform and three-dimensional |
| B. | Steady, uniform, two-dimensional |
| C. | Unsteady, uniform, three-dimensional |
| D. | Unsteady, non-uniform and three-dimensional. |
| Answer» E. | |
| 114. |
The motion is described as ......when the components of rotation or vorticity are zero throughout certain point of the fluid. |
| A. | Rotational |
| B. | Irrotational |
| C. | Either of the above |
| D. | None of the above. |
| Answer» C. Either of the above | |
| 115. |
The viscosity of liquids ..... with increase in temperature. |
| A. | Decreases |
| B. | Increases |
| C. | First decreases and then increases |
| D. | First increases and then decreases. |
| Answer» B. Increases | |
| 116. |
When a body is immersed in a fluid, partially or completely, the force of buoyancy is equal to |
| A. | The weight of the body |
| B. | The weight of the fluid displaced by the body |
| C. | The weight of the volume of the fluid equal to the volume of body |
| D. | None of the above. |
| Answer» C. The weight of the volume of the fluid equal to the volume of body | |
| 117. |
The water which acts on the runner blades of a reaction turbine is under a pressure |
| A. | Equal to atmospheric |
| B. | Below atmospheric |
| C. | Above atmospheric |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 118. |
Which of the following statements is correct? Wall turbulence occurs |
| A. | In immediate vicinity of solid surfaces and in the boundary layer flows where the fluid has a negligible mean acceleration |
| B. | In jets, wakes, mixing layer etc. |
| C. | Where there is conversion of potential energy into kinetic energy by the process of mixing |
| D. | None of the above. |
| Answer» B. In jets, wakes, mixing layer etc. | |
| 119. |
With reference to a centrifugal pump which of the following statements is incorrect? |
| A. | The discharge control valve is fitted in the delivery pipe. |
| B. | The suction pipe is provided with a foot valve and a strainer. |
| C. | The suction pipe has larger diameter as compared to the discharge pipe. |
| D. | The discharge control valve is fitted in the suction pipe. |
| Answer» E. | |
| 120. |
........ is the square root of the ratio of the inertia force to the pressure force. |
| A. | Reynolds number |
| B. | Mach’s number |
| C. | Euler’s number |
| D. | Froude’s number. |
| Answer» D. Froude’s number. | |
| 121. |
A Kaplan turbine claims which of the following advantages over a Francis turbine? |
| A. | More compact in construction and smaller in size. |
| B. | Partload efficiency is considerably high. |
| C. | Low frictional losses. |
| D. | All of the above. |
| Answer» E. | |
| 122. |
The motion of fluid particles may be described by which of the following methods? |
| A. | Langrangian method |
| B. | Eulerain method |
| C. | Both (a) and (b) |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 123. |
The flow in a pipe whose valve is being opened or closed gradually is an example of |
| A. | Steady flow |
| B. | Unsteady flow |
| C. | Rotational flow |
| D. | Compressible flow. |
| Answer» C. Rotational flow | |
| 124. |
A solid can resist which of the following stresses? |
| A. | Tensile |
| B. | Compressive |
| C. | Shear |
| D. | All of the above. |
| Answer» E. | |
| 125. |
Which of the following turbines is most efficient at partload operation? |
| A. | Kaplan |
| B. | Propeller |
| C. | Francis |
| D. | Pelton wheel. |
| Answer» B. Propeller | |
| 126. |
The shear in turbulent flow is mainly due to |
| A. | Heat transfer |
| B. | Mass transfer |
| C. | Momentum transfer |
| D. | All of the above. |
| Answer» D. All of the above. | |
| 127. |
With reference to manometric head which of the following statements is correct? |
| A. | It is the head developed by the pump. |
| B. | It is the height to which water is lifted by the pump measured above the pump centreline. |
| C. | it is the difference in elevation between the water surface in the high level reservoir and the water level in the sump. |
| D. | It is the difference in the piezometric heads between the points on the delivery and suction pipes as close to the pump as possible. |
| Answer» E. | |
| 128. |
The type of flow in which the velocity at any given time does not change with respect to space is called |
| A. | Steady flow |
| B. | Compressible flow |
| C. | Uniform flow |
| D. | Rotational flow. |
| Answer» D. Rotational flow. | |
| 129. |
The capillary rise of water in the glass tube is given by |
| A. | h = 2σ/wd |
| B. | h = 3σ/wd |
| C. | h = 4σ/wd |
| D. | h = 6σ/wd |
| Answer» D. h = 6σ/wd | |
| 130. |
A turbulent flow is considered steady when |
| A. | The algebraic sum of velocity fluctuations is zero |
| B. | The velocity at a point does not change with Time |
| C. | Temporal mean velocity at a point remains constant with time |
| D. | The discharge remains constant. |
| Answer» D. The discharge remains constant. | |
| 131. |
Dynamic similarity between the model and prototype is the |
| A. | Similarity of motion |
| B. | Similarity of lengths |
| C. | Similarity of forces |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 132. |
Bulk modulus of elasticity is the ratio of |
| A. | Tensile stress to tensile strain |
| B. | Compressive stress to compressive strain |
| C. | Compressive stress to volumetric strain |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 133. |
For an impulse turbine which of the following statements is correct : |
| A. | It makes use of a draft tube |
| B. | It is not exposed to atmosphere |
| C. | It is most suited for low head installations |
| D. | It operates with initial complete conversion of pressure head to velocity head. |
| Answer» E. | |
| 134. |
A Kaplan turbine is |
| A. | An inward flow impulse turbine |
| B. | Low head axial flow turbine |
| C. | High head axial flow turbine |
| D. | High head mixed flow turbine. |
| Answer» C. High head axial flow turbine | |
| 135. |
A surge tank is used to |
| A. | Prevent occurrence of hydraulic jump |
| B. | Smoothen the flow |
| C. | Relieve the pipeline of excessive pressure transients |
| D. | Avoid reversal of flow. |
| Answer» D. Avoid reversal of flow. | |
| 136. |
. ...... is a phenomenon by which a liquid rises into a thin glass tube above or below its general level. |
| A. | Surface tension |
| B. | Capillarity |
| C. | Cohesion |
| D. | Adhesion. |
| Answer» C. Cohesion | |
| 137. |
In order that results obtained in model studies correctly represent the behaviour of the prototype, which of the following similarities must be ensured between the model and the prototype? |
| A. | Geometric similarity |
| B. | Kinematic similarity |
| C. | Dynamic similarity |
| D. | All of the above. |
| Answer» E. | |
| 138. |
The condition for maximum transmission of power through a pipeline is that one-third of the availablehead must be consumed in friction. The corresponding efficiency of the pipeline is |
| A. | 33·3% |
| B. | 66·67% |
| C. | 90% |
| D. | 100%. |
| Answer» C. 90% | |
| 139. |
The magnitude of the buoyant force can be determined by |
| A. | Newton’s second law of motion |
| B. | Archimedes’ principle |
| C. | Principle of moments |
| D. | None of the above. |
| Answer» C. Principle of moments | |
| 140. |
Elasticity of fluids is measured in terms of |
| A. | Young’s modulus of elasticity |
| B. | Shear modulus of elasticity |
| C. | Bulk modulus of elasticity |
| D. | None of the above. |
| Answer» D. None of the above. | |
| 141. |
If a body does not return to its original position from the slightly displaced angular position and heels farther away, when given a small angular displacement; such an equilibrium is called |
| A. | Stable equilibrium |
| B. | Unstable equilibrium |
| C. | Neutral equilibrium |
| D. | Any of the above |
| Answer» C. Neutral equilibrium | |
| 142. |
The specific speed of a pump is defined as the speed of unit of such a size that it |
| A. | Produces unit power with unit head available |
| B. | Delivers unit discharge at unit head |
| C. | Requires unit power to develop unit head |
| D. | Delivers unit discharge at unit power. |
| Answer» C. Requires unit power to develop unit head | |
| 143. |
In case of viscous flow through circular pipes |
| A. | ͞u = 2 umax |
| B. | u = (3/2) umax |
| C. | u = umax/2 |
| D. | none of the above. |
| Answer» C. u = umax/2 | |
| 144. |
Which of the following is an example of phenomenon of surface tension? |
| A. | Rain drops |
| B. | Rise of sap in a tree |
| C. | Break up of liquid jets |
| D. | All of the above. |
| Answer» E. | |
| 145. |
Euler number is important in which of the following flow situations? |
| A. | Discharge through orifices, mouthpieces and sluices |
| B. | Pressure rise due to sudden closure of valves |
| C. | Flow through pipes |
| D. | All of the above |
| Answer» E. | |
| 146. |
In case of a turbulent flow, the loss of head is approximately proportional to |
| A. | Velocity |
| B. | (Velocity) ^1/2 |
| C. | (Velocity) ^3/4 |
| D. | (Velocity) ^2 |
| Answer» E. | |
| 147. |
In rotodynamic pumps, the increase in energy level is due to |
| A. | Centrifugal energy only |
| B. | Pressure energy only |
| C. | Kinetic energy only |
| D. | Combination of a, b and c. |
| Answer» E. | |
| 148. |
Which of the following factors determine the friction factor for turbulent flow in a rough pipe? |
| A. | Mach number and relative roughness |
| B. | Froude’s number and Mach’s number |
| C. | Reynolds number and relative roughness |
| D. | Froude’s number and relative roughness. |
| Answer» D. Froude’s number and relative roughness. | |
| 149. |
The property of a fluid which determines its resistance to shearing stress is called |
| A. | Viscosity |
| B. | Surface tension |
| C. | Compressibility |
| D. | None of the above. |
| Answer» B. Surface tension | |
| 150. |
In which of the following measuring devices Bernoulli’s equation is used: |
| A. | Venturimeter |
| B. | Orificemeter |
| C. | Pitot tube |
| D. | All the above. |
| Answer» E. | |