MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 8247 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 4151. |
Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around |
| A. | 2000 |
| B. | 10 |
| C. | 100 |
| D. | 1000 |
| Answer» E. | |
| 4152. |
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. | |
| 4153. |
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. | |
| 4154. |
In which type of fluid flow, the velocity of flow of fluid changes from point to point in the fluid at any instant ? |
| A. | Rotational |
| B. | Unsteady |
| C. | Turbulent |
| D. | Non-uniform |
| Answer» E. | |
| 4155. |
The continuity equation in ideal fluid flow states that |
| A. | net rate of inflow into any small volume must be zero. |
| B. | energy is not constant along a streamline. |
| C. | energy is constant along a streamline. |
| D. | there exists a velocity potential. |
| Answer» B. energy is not constant along a streamline. | |
| 4156. |
Pitot tube measures the __________ of a fluid. |
| A. | pressure |
| B. | average velocity |
| C. | average flow rate |
| D. | point velocity |
| Answer» E. | |
| 4157. |
Which of the following is not dimension-less? |
| A. | Froude number |
| B. | Kinematic viscosity |
| C. | Pressure co-efficient |
| D. | None of these |
| Answer» C. Pressure co-efficient | |
| 4158. |
In laminar flow through a round tube, the discharge varies |
| A. | linearly as the viscosity. |
| B. | inversely as the pressure drop. |
| C. | inversely as the viscosity. |
| D. | as the square of the radius. |
| Answer» D. as the square of the radius. | |
| 4159. |
Which is not a variable head meter ? |
| A. | Venturimeter |
| B. | Pitot tube |
| C. | Rotameter |
| D. | None of these |
| Answer» D. None of these | |
| 4160. |
Viscosity of water is about __________ times that of air at room temperature. |
| A. | 15 |
| B. | 55 |
| C. | 155 |
| D. | 1050 |
| Answer» C. 155 | |
| 4161. |
Net positive suction head (NPSH) of a centrifugal pump must be |
| A. | greater than the vapour pressure of the liquid. |
| B. | less than the vapour pressure of the liquid. |
| C. | equal to the vapour pressure of the liquid. |
| D. | less than barometric pressure. |
| Answer» B. less than the vapour pressure of the liquid. | |
| 4162. |
Actual lift of a pump is always less than the theoretical lift and is limited by the |
| A. | specific gravity & temperature of the liquid. |
| B. | leakage & pressure decreasing at higher elevations. |
| C. | frictional resistance through pipes, fittings & passages. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 4163. |
In case of unsteady fluid flow, conditions & flow pattern change with the passage of time at a position in a flow situation. Which of the following is an example of unsteady flow? |
| A. | Discharge of water by a centrifugal pump being run at a constant rpm. |
| B. | Water flow in the suction and discharge pipe of a reciprocating pump. |
| C. | Water discharge from a vertical vessel in which constant level is maintained. |
| D. | Low velocity flow of a highly viscous liquid through a hydraulically smooth pipe. |
| Answer» C. Water discharge from a vertical vessel in which constant level is maintained. | |
| 4164. |
Nature of fluid flow during the opening of a valve in a pipeline is |
| A. | laminar |
| B. | unsteady |
| C. | steady |
| D. | uniform |
| Answer» C. steady | |
| 4165. |
For motion of spherical particles in a stationary fluid, the drag co-efficient in hindered settling compared to that in free settling is |
| A. | more |
| B. | less |
| C. | equal |
| D. | more or less, depending on the type of particle |
| Answer» B. less | |
| 4166. |
Specific speed of a centrifugal pump relates it with another pump having the |
| A. | dynamic similarity |
| B. | same efficiency |
| C. | same speed |
| D. | geometrical similarity |
| Answer» B. same efficiency | |
| 4167. |
The pressure drop per unit length of pipe incurred by a fluid 'X' flowing through pipe is p. If another fluid 'Y' having both the specific gravity & density just double of that of fluid 'X', flows through the same pipe at the same flow rate/average velocity, then the pressure drop in this case will be |
| A. | p |
| B. | 2 p |
| C. | p |
| D. | <sup>2</sup> |
| E. | p/2 |
| Answer» C. p | |
| 4168. |
Fluid flow in a/an __________ is an example of pressure flow. |
| A. | partially filled pipeline |
| B. | pipe |
| C. | open channel |
| D. | river. |
| Answer» C. open channel | |
| 4169. |
In the laminar boundary layer flow over a flat plate, the ratio ( /x) varies as :(where, ' ' is the boundary layer thickness and 'x' is the distance from the leading edge in the direction of flow). |
| A. | Re |
| B. | <span class="root"> Re</span> |
| C. | 1/Re |
| D. | Re |
| E. | <sup>-1/2</sup> |
| Answer» E. <sup>-1/2</sup> | |
| 4170. |
A rotameter through which air at room temperature and atmospheric pressure is flowing gives a certain reading for a flow rate of 100 cc/sec. If helium (molecular weight 4) is used and rotameter shows the same reading, the flow rate (cc/sec) is |
| A. | 26 |
| B. | 42 |
| C. | 269 |
| D. | 325 |
| Answer» D. 325 | |
| 4171. |
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 | |
| 4172. |
A fluid is the one, which |
| A. | cannot remain at rest under the action of shear force. |
| B. | continuously expands till it fills any container. |
| C. | is incompressible. |
| D. | permanently resists distortion. |
| Answer» B. continuously expands till it fills any container. | |
| 4173. |
One horsepower is equal to |
| A. | 550 lbf.ft/second |
| B. | 550 kgf.m/second |
| C. | both (a) and (b) |
| D. | 550 lbf.ft./hr |
| Answer» B. 550 kgf.m/second | |
| 4174. |
For one dimensional flow of an incompressible fluid in unsteady state in x-direction, the continuity equation is given by |
| A. | <img src="/_files/images/chemical-engineering/fluid-mechanics/46-650-1.png"> |
| B. | <img src="/_files/images/chemical-engineering/fluid-mechanics/46-650-2.png"> |
| C. | <img src="/_files/images/chemical-engineering/fluid-mechanics/46-650-3.png"> |
| D. | <img src="/_files/images/chemical-engineering/fluid-mechanics/46-650-4.png"> |
| Answer» B. <img src="/_files/images/chemical-engineering/fluid-mechanics/46-650-2.png"> | |
| 4175. |
A fluidis moving at critical flow condition (NRe = 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 | |
| 4176. |
Capillary rise of mercury in a small diameter tube is proportional to (where, d = diameter of the tube, = surface tension of mercury) |
| A. | <i>d</i> |
| B. | 1/ |
| C. | <i>d </i> |
| D. | |
| E. | l/ |
| Answer» D. | |
| 4177. |
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 | |
| 4178. |
The kinetic energy correction factor for velocity distribution of laminar flow is |
| A. | 0.5 |
| B. | 1.66 |
| C. | 1 |
| D. | 2 |
| Answer» C. 1 | |
| 4179. |
Priming of a centrifugal pump is done to |
| A. | increase the mass flow rate of fluid. |
| B. | develop effective pressure rise by the pump. |
| C. | avoid chances of separation inside the impeller. |
| D. | none of these. |
| Answer» D. none of these. | |
| 4180. |
Bed pressure drop in an air fluidised bed of catalyst particles ( p = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is |
| A. | 90 |
| B. | 60 |
| C. | 45 |
| D. | 30 |
| Answer» C. 45 | |
| 4181. |
For pipes that must be broken at intervals for maintenance, the connector used should be a/an |
| A. | union |
| B. | tee |
| C. | reducer |
| D. | elbow |
| Answer» B. tee | |
| 4182. |
Cavitation can be prevented by |
| A. | suitably designing the pump. |
| B. | maintaining the suction head sufficiently greater than the vapour pressure. |
| C. | maintaining suction head = developed head. |
| D. | maintaining suction head lower than the vapour pressure. |
| Answer» C. maintaining suction head = developed head. | |
| 4183. |
Assuming flow to be laminar, if the diameter of the pipe is halved, then the pressure drop will |
| A. | increase |
| B. | decrease |
| C. | remain same |
| D. | be quadrupled |
| Answer» B. decrease | |
| 4184. |
Steady flow occurs, when the |
| A. | conditions change steadily with time. |
| B. | conditions are the same at the adjacent points at any instant. |
| C. | conditions do not change with time at any point. |
| D. | rate of the velocity change is constant. |
| Answer» D. rate of the velocity change is constant. | |
| 4185. |
With increase in the ratio of orifice diameter to pipe diameter, the fraction of the orifice pressure differential that is permanently lost |
| A. | increases |
| B. | decreases |
| C. | remains unchanged |
| D. | increases exponentially |
| Answer» C. remains unchanged | |
| 4186. |
Permanent loss in a venturimeter is about __________ percent of the pressure drop in theupstream cone. |
| A. | 1 |
| B. | 10 . |
| C. | 40 |
| D. | 70 |
| Answer» C. 40 | |
| 4187. |
Volume of liquid displaced by a floating body is equivalent to its |
| A. | own weight |
| B. | submerged weight |
| C. | own volume |
| D. | submerged volume |
| Answer» B. submerged weight | |
| 4188. |
Venturimeters, orificemeters and nozzles are used to measure the fluid discharge from a pipeline. The average fluid velocity in a pipeline can be measured by a/an |
| A. | weir |
| B. | hot wire anemometer |
| C. | cup and vane aneometer |
| D. | none of these |
| Answer» C. cup and vane aneometer | |
| 4189. |
The time taken for gravity flow of a fixed volume of liquid (as in Redwood viscometer) is directly proportional to its |
| A. | absolute viscosity. |
| B. | ratio of absolute viscosity to density. |
| C. | density. |
| D. | Reynolds number. |
| Answer» C. density. | |
| 4190. |
The exit cone angle in case of a standard venturimeter is __________ the entrance cone angle. |
| A. | smaller than |
| B. | greater than |
| C. | equal to |
| D. | either (a) or (b) |
| Answer» B. greater than | |
| 4191. |
Sewage sludge is __________ type of non-Newtonion fluid. |
| A. | dilatant |
| B. | Bingham plastic |
| C. | Pseudo plastic |
| D. | none of these |
| Answer» C. Pseudo plastic | |
| 4192. |
Ratio of pressure and inertia force gives __________ number. |
| A. | Weber |
| B. | Mach |
| C. | Euler |
| D. | Froude |
| Answer» D. Froude | |
| 4193. |
With increase in pump speed, its NPSH requirement |
| A. | decreases |
| B. | increases |
| C. | remains unaltered |
| D. | can either increase or decrease ; depends on other factors |
| Answer» C. remains unaltered | |
| 4194. |
In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. |
| A. | directly proportional to |
| B. | inversely proportional to |
| C. | inversely proportional to the square root of |
| D. | independent of |
| Answer» C. inversely proportional to the square root of | |
| 4195. |
Gear pump |
| A. | is a positive displacement pump. |
| B. | is a centrifugal pump. |
| C. | is a non-positive displacement pump. |
| D. | can be started with delivery valve closed. |
| Answer» B. is a centrifugal pump. | |
| 4196. |
Most of the centrifugal pumps used in chemical plants are usually __________ driven. |
| A. | steam |
| B. | diesel engine |
| C. | electric motor |
| D. | gas turbine |
| Answer» D. gas turbine | |
| 4197. |
Check valve provided in the discharge line of a centrifugal pump serves the purpose of controlling the |
| A. | back flow of fluid in the event of stoppage of pump. |
| B. | discharge pressure. |
| C. | flow of liquid during operation of the pump. |
| D. | all (a), (b) and (c). |
| Answer» B. discharge pressure. | |
| 4198. |
Medium viscosity lubricating oil can be most ideally pumped by a __________ pump. |
| A. | vane |
| B. | piston |
| C. | centrifugal |
| D. | plunger |
| Answer» B. piston | |
| 4199. |
Pump used for the transportation of molten sodium in a fast breader reactor is a/an __________ pump. |
| A. | reciprocating |
| B. | plunger |
| C. | electromagnetic |
| D. | gear |
| Answer» D. gear | |
| 4200. |
Small pressure differences in liquids is measured using a/an |
| A. | U-tube manometer. |
| B. | inclined tube manometer. |
| C. | pitot tube. |
| D. | none of these. |
| Answer» C. pitot tube. | |