MCQOPTIONS
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MCQOPTIONS
This section includes 243 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 201. |
What happens to the head loss when the flow rate is doubled? |
| A. | doubles |
| B. | same |
| C. | triples |
| D. | four times |
| Answer» E. | |
| 202. |
What are the reasons for minor head loses in a pipe? |
| A. | friction |
| B. | heat |
| C. | valves and bends |
| D. | temperature |
| Answer» D. temperature | |
| 203. |
The formula for hydraulic diameter is |
| A. | 4a/p |
| B. | 4ap |
| C. | 4av |
| D. | 4v |
| Answer» B. 4ap | |
| 204. |
Loss of head due to friction is |
| A. | directly proportional to hydraulic radius |
| B. | inversely proportional to velocity |
| C. | inversely proportional to hydraulic radius |
| D. | directly proportional to gravitational constant |
| Answer» D. directly proportional to gravitational constant | |
| 205. |
Which among the following is formula for friction factor of circular pipes? |
| A. | 16/re |
| B. | 64/re |
| C. | re/16 |
| D. | re/64 |
| Answer» C. re/16 | |
| 206. |
Darcy- Weisbach equation gives relation between |
| A. | pressure and temperature |
| B. | mass, volume and pressure |
| C. | head loss and pressure loss |
| D. | pressure loss only |
| Answer» D. pressure loss only | |
| 207. |
How do we calculate losses for a larger range of Reynolds number? |
| A. | moody chart |
| B. | bar chart |
| C. | scatter chart |
| D. | column histogram |
| Answer» B. bar chart | |
| 208. |
depend on the friction factor? |
| A. | pipe diameter |
| B. | fluid density |
| C. | viscosity |
| D. | weight |
| Answer» E. | |
| 209. |
What is D’Alembert’s Paradox? |
| A. | resistance= 0 |
| B. | drag force= 0 |
| C. | temperature = 0 |
| D. | pressure gradient= 0 |
| Answer» C. temperature = 0 | |
| 210. |
automatic control scheme during the fluid flow? |
| A. | rotameters |
| B. | pulley plates |
| C. | rotary piston |
| D. | pilot static tube |
| Answer» E. | |
| 211. |
The steady- state flow must satisfy |
| A. | kirchhoff’s law |
| B. | newtons law |
| C. | rutherford’s experiment |
| D. | kepler’s law |
| Answer» B. newtons law | |
| 212. |
With the boundary layer separation, displacement thickness |
| A. | increases |
| B. | decreases |
| C. | remains same |
| D. | independent |
| Answer» B. decreases | |
| 213. |
Boundary layer separation does not undergo detachment. |
| A. | true |
| B. | false |
| Answer» C. | |
| 214. |
Which among the following is a device that converts a laminar flow into a turbulent flow? |
| A. | dead weight gauge |
| B. | vacuum gauge |
| C. | turbulator |
| D. | ionization gauge |
| Answer» D. ionization gauge | |
| 215. |
The flow separation occurs when the fluid travels away from the |
| A. | surface |
| B. | fluid body |
| C. | adverse pressure gradient |
| D. | inter-molecular spaces |
| Answer» D. inter-molecular spaces | |
| 216. |
Eddy viscosity is a turbulent transfer of |
| A. | fluid |
| B. | heat |
| C. | momentum |
| D. | pressure |
| Answer» D. pressure | |
| 217. |
The swirl caused due to eddies are called as |
| A. | vortices |
| B. | vertices |
| C. | volume |
| D. | velocity |
| Answer» B. vertices | |
| 218. |
Which of the following flows have the highest critical Reynolds number (lower)? |
| A. | flow in a pipe |
| B. | flow between parallel plates |
| C. | flow in an open channel |
| D. | flow around spherical body |
| Answer» B. flow between parallel plates | |
| 219. |
A circular pipe of radius 7 cm is used for water flow transmission. This pipe is moulded into another pipe with a square cross-section keeping the length same. (Ignore the thickness of the pipe). Calculate the hydraulic diameter of the moulded pipe. (Take π = 22/7). |
| A. | 11 cm |
| B. | 7 cm |
| C. | 3.5 cm |
| D. | 22 cm |
| Answer» B. 7 cm | |
| 220. |
What can be the maximum diameter of the pipe for the water flow of velocity 1 m/s (ν = 10-6) to be laminar in nature? Assume Lower critical Reynolds number to be 2100. |
| A. | 2.1 mm |
| B. | 21 mm |
| C. | 21 cm |
| D. | 0.21 mm |
| Answer» B. 21 mm | |
| 221. |
The flow through a circular pipe is laminar. Now, the fluid through the pipe is replaced with a more viscous fluid and passed through the pipe again with the same velocity. What can we say about the nature of this flow? |
| A. | the flow will become turbulent |
| B. | the flow will be a transition flow |
| C. | the flow will remain laminar |
| D. | the reynolds number of the earlier flow is required to answer this question |
| Answer» D. the reynolds number of the earlier flow is required to answer this question | |
| 222. |
The Reynolds number is found out for a flow in a circular pipe. This circular pipe is moulded into a square pipe, keeping length of the pipe same. Ignore the thickness of the pipe. The Reynolds number changes by |
| A. | 57% decrease |
| B. | 57% increase |
| C. | 43% decrease |
| D. | 43% increase |
| Answer» C. 43% decrease | |
| 223. |
How is Reynolds number defined as? |
| A. | ratio of pressures in the inlet to the outlet of a pipe |
| B. | the product of velocity of the flow and the diameter of the pipe, divided by the kinematic viscosity of fluid |
| C. | the product of density of the fluid, velocity of the flow and the diameter of the pipe, divided by the dynamic viscosity of fluid |
| D. | ratio of inertia force to viscous force |
| Answer» E. | |
| 224. |
Which of the factors primarily decide whether the flow in a circular pipe is laminar or turbulent? |
| A. | the prandtl number |
| B. | the pressure gradient along the length of the pipe |
| C. | the dynamic viscosity coefficient |
| D. | the reynolds number |
| Answer» E. | |
| 225. |
When a problem states “The velocity of the water flow in a pipe is 20 m/sâ€, which of the following velocities is it talking about? |
| A. | rms velocity |
| B. | average velocity |
| C. | absolute velocity |
| D. | relative velocity |
| Answer» C. absolute velocity | |
| 226. |
the pressure vary with the length of the pipe? |
| A. | linearly |
| B. | parabolic |
| C. | exponential |
| D. | constant |
| Answer» B. parabolic | |
| 227. |
between EGL and HGL |
| A. | increases |
| B. | decreases |
| C. | remains constant |
| D. | may increase or decrease |
| Answer» C. remains constant | |
| 228. |
For a nozzle, the vertical intercept between EGL and HGL |
| A. | increases |
| B. | decreases |
| C. | remains constant |
| D. | may increase or decrease |
| Answer» B. decreases | |
| 229. |
The slope of HGL will be |
| A. | greater than that of egl for a pipe of uniform cross-section |
| B. | smaller than that of egl for a pipe of uniform cross-section |
| C. | equal than that of egl for a pipe of uniform cross-section |
| D. | independent of that of egl for a pipe of uniform cross-section |
| Answer» D. independent of that of egl for a pipe of uniform cross-section | |
| 230. |
The vertical intercept between EGL and HGL is equal to |
| A. | pressure head |
| B. | potential head |
| C. | kinetic head |
| D. | piezometric head |
| Answer» D. piezometric head | |
| 231. |
Hydraulic gradient line takes into consideration |
| A. | potential and kinetic heads only |
| B. | potential and pressure heads only |
| C. | kinetic and pressure heads only |
| D. | potential, kinetic and pressure heads |
| Answer» C. kinetic and pressure heads only | |
| 232. |
ÏV→. dS→ is positive when |
| A. | the mass flow is outward |
| B. | the mass flow is inward |
| C. | the mass flow is positive |
| D. | the mass flow is negative |
| Answer» B. the mass flow is inward | |
| 233. |
equation of mass conservation into the conservative integral form, which of these theorems is used? |
| A. | stokes theorem |
| B. | kelvin-stokes theorem |
| C. | gauss-siedel theorem |
| D. | gauss divergence theorem |
| Answer» E. | |
| 234. |
continuity equation is |
| A. | mass conservation |
| B. | zeroth law of thermodynamics |
| C. | first law of thermodynamics |
| D. | energy conservation |
| Answer» B. zeroth law of thermodynamics | |
| 235. |
mark of one litre and weighed. The weight of the liquid is found to be 6.5 N. The specific volume of the liquid will be |
| A. | 1 l =kg |
| B. | 1:5 l =kg |
| C. | 2 l =kg |
| D. | 2:5 l =kg |
| Answer» C. 2 l =kg | |
| 236. |
A beaker is filled with a liquid up to the mark of one litre and weighed. The weight of the liquid is found to be 6.5 N. The specific gravity of the liquid will be |
| A. | 0.65 |
| B. | 0.66 |
| C. | 0.67 |
| D. | 0.68 |
| Answer» C. 0.67 | |
| 237. |
mark of one litre and weighed. The weight of the liquid is found to be 6.5 N. The specific weight of the liquid will be |
| A. | 6:5 kn = m3 |
| B. | 6:6 kn = m3 |
| C. | 6:7 kn = m3 |
| D. | 6:8 kn = m3 |
| Answer» B. 6:6 kn = m3 | |
| 238. |
the relation between their specific volumes v1 and v2? |
| A. | v1 > v2 |
| B. | v1 < v2 |
| C. | v1 = v2 |
| D. | cannot be determined due to insufficient information. |
| Answer» C. v1 = v2 | |
| 239. |
[p] = [m]/[v] = [m] /[L3] = [ML-3]. |
| A. | [m1 l-3 t0]. |
| B. | [m1 l0 t0]. |
| C. | [m0 l-3 t0]. |
| D. | [m0 l0 t0]. |
| Answer» E. | |
| 240. |
Which one of the following is the |
| A. | [m1 l-3 t0]. |
| B. | [m-1 l3 t0]. |
| C. | [m-1 l-3 t0]. d) [m0 l3 t0]. |
| Answer» C. [m-1 l-3 t0]. d) [m0 l3 t0]. | |
| 241. |
Which one of the following is the unit of specific weight? |
| A. | n = m3 |
| B. | n = m2 |
| C. | n = m |
| D. | n = ms |
| Answer» B. n = m2 | |
| 242. |
The specific gravity of a liquid has |
| A. | the same unit as that of mass density |
| B. | the same unit as that of weight density |
| C. | the same unit as that of specific volume |
| D. | no unit |
| Answer» E. | |
| 243. |
The specific volume of a liquid is the reciprocal of |
| A. | weight density |
| B. | mass density |
| C. | specific weight |
| D. | specific volume |
| Answer» C. specific weight | |