91
Mach number is significant in
A)
Supersonics, as with projectiles and jet propulsion
B)
Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.
C)
Simultaneous motion through two fluids where there is a surface of discontinuity, gravity force, and wave making effects, as with ship's hulls
D)
All of the above
Answer & Solution
Answer: Option
A
92
A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction of it volume is under mercury?
A)
The metal piece will simply float over the mercury
B)
The metal piece will be immersed in mercury by half
C)
Whole of the metal piece will be immersed with its top surface just at mercury level
D)
Metal piece will sink to the bottom
Answer & Solution
Answer: Option
C
93
A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6. What fraction of its volume is under mercury?
A)
0.5
B)
0.4
C)
0.515
D)
0.3
Answer & Solution
Answer: Option
C
94
The power transmitted through a pipe is (where w = Specific weight in N/m3 and Q = Discharge in m3 /s)
A)
$${\text{w}} \times {\text{Q}} \times {\text{H}}$$
B)
$${\text{w}} \times {\text{Q}} \times {{\text{h}}_{\text{f}}}$$
C)
$${\text{w}} \times {\text{Q}}\left( {{\text{H}} - {{\text{h}}_{\text{f}}}} \right)$$
D)
$${\text{w}} \times {\text{Q}}\left( {{\text{H}} + {{\text{h}}_{\text{f}}}} \right)$$
Answer & Solution
Answer: Option
C
95
In a single casing, multistage pump running at constant speed, the capacity rating is to be slightly lowered. It can be done by
A)
Designing new impeller
B)
Trimming the impeller size to the required size by machining
C)
Not possible
D)
Some other alterations in the impeller
Answer & Solution
Answer: Option
B
96
An air vessel is provided at the summit in a siphon to
A)
Avoid interruption in the flow
B)
Increase discharge
C)
Increase velocity
D)
Maintain pressure difference
Answer & Solution
Answer: Option
A
97
In a free vortex motion, the radial component of velocity everywhere is
A)
Maximum
B)
Minimum
C)
Zero
D)
Nonzero and finite
Answer & Solution
Answer: Option
C
98
The celerity (velocity) of a pressure wave in a fluid is given by (where K = Bulk modulus and $$\rho $$ = Density of the fluid)
A)
$${\text{K}} \times \rho $$
B)
$$\frac{{\text{K}}}{\rho }$$
C)
$$\frac{\rho }{{\text{K}}}$$
D)
None of these
Answer & Solution
Answer: Option
B
99
When a cylindrical vessel containing liquid is revolved about its vertical axis at a constant angular velocity, the pressure
A)
Varies as the square of the radial distance
B)
Increases linearly as its radial distance
C)
Increases as the square of the radial distance
D)
Decreases as the square of the radial distance
Answer & Solution
Answer: Option
A
100
A fluid in equilibrium can't sustain
A)
Tensile stress
B)
Compressive stress
C)
Shear stress
D)
Bending stress
Answer & Solution
Answer: Option
C
