Fluid Mechanics

231.For water, when the pressure increases, the viscosity

1. Also increases
2. Decreases
3. Remain constant
4. First decreases, and then increases

View answer

232.Forces acting on a particle settling in fluid are _________ forces.

1. Gravitational & buoyant
2. Centrifugal & drag
3. Gravitational or centrifugal buoyant drag
4. External, drag & viscous

View answer

233.Friction factor for a hydraulically smooth pipe at N_Re = 2100 is f1. If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of N_Re, will

1. Increase
2. Decrease
3. Remain unchanged
4. Increase or decrease depending on the pipe material

View answer

234.Friction produced by the formation of wakes is called the _________ friction.

1. Disk
2. Skin
3. Form
4. None of these

View answer

235.Froude number is not a factor

1. For Reynolds number greater than 300
2. When there is no vortex formation
3. For unbaffled tank
4. None of these

View answer

236.Froude number is the ratio of

1. Shear stress to gravitational stress
2. Drag stress to shear stress
3. Inertial stress to shear stress
4. Inertial stress to gravitational stress

View answer

237.Function of air vessel provided in a reciprocating pump is to

1. Reduce discharge fluctuation
2. Reduce the danger of cavitation
3. Avoid the necessity of priming
4. Increase the pump efficiency

View answer

238.Gear pump

1. Is a positive displacement pump
2. Is a centrifugal pump
3. Is a non-positive displacement pump
4. Can be started with delivery valve closed

View answer

239.Glass pipes can be joined by

1. Flanges
2. Welding
3. Soldering
4. Bell and spigot joint

View answer

240.Gradually varied flow in open channel is a/an _________ flow.

1. Steady uniform
2. Steady non-uniform
3. Unsteady uniform
4. Unsteady non-uniform

View answer