The power absorbed (in watts) in overcoming the viscous resistance of a footstep bearing is
μ π³ N² R² /1800 t
μ π³ N² R⁴ /1800 t
μ π³ N² R² /3600 t
μ π³ N² R⁴ /3600 t
Correct Answer :
B. μ π³ N² R⁴ /1800 t
Related Questions
The maximum efficiency of transmission through a pipe is
50 %
56.7 %
66.67 %
76.66 %
When a body is immersed wholly or partially in a liquid, it is lifted up by a force equal to the weight of liquid displaced by the body. This statement is called
Pascal's law
Archimedess principle
Principle of floatation
Bernoulli's theorem
The speed of sound in a ideal gas varies directly as its
Absolute temperature
Temperature
Density
Modulus of elasticity
Hot wire anemometer is used to measure
Pressure in gases
Liquid discharge
Pressure in liquids
Gas velocities
The centre of gravity of the volume of the liquid displaced by an immersed body is called
Centre of gravity
Centre of pressure
Metacentre
Centre of buoyancy
The stress-strain relation of the Newtonian fluid is
Linear
Parabolic
Hyperbolic
Inverse type
The ratio of the inertia force to the elastic force is called
Reynold's number
Froude's number
Weber's number
Mach number
In a lock-gate, the reaction between two gates is (where P = Resultant pressure on the lock gate, and α = Inclination of the gate with the normal to the side of the lock)
p/sinα
2p/sinα
p/2sinα
2p/sin (α/2)
One cubic metre of water weighs
100 litres
250 litres
500 litres
1000 litres
The units of kinematic viscosity are
Metres² per sec
kg sec/metre
Newton-sec per metre
Newton-sec per metre
The purpose of a surge tank is
To control the pressure variations due to rapid changes in the pipe line flow
To eliminate water hammer possibilities
To regulate flow of water to turbines by providing necessary retarding head of water
All of the above
An object having 10 kg mass weighs 9.81 kg on a spring balance. The value of 'g' at this place is
10 m/sec²
9.81 m/sec²
9.75 m/sec²
9 m/sec
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a triangular notch is given by
dQ/Q = 3/2 × (dH/H)
dQ/Q = 2 × (dH/H)
dQ/Q = 5/2 × (dH/H)
dQ/Q = 3 × (dH/H)
The process of diffusion of one liquid into the other through a semi permeable membrane is called
Viscosity
Osmosis
Surface tension
Cohesion
Euler's dimensionless number relates the following
Inertial force and gravity
Viscous force and inertial force
Viscous force and buoyancy force
Pressure force and inertial force
The critical depth for a channel is given by (where q = Unit discharge (discharge per unit width) through the channel)
(q/g)1/2
(q²/g)1/3
(q³/g)1/4
(q⁴/g)1/5
A notch is used to measure __________ of liquids.
Pressure
Discharge
Velocity
Volume
The total energy of each particle at various places in the case of perfect incompressible fluid flowing in continuous stream
Keeps on increasing
Keeps on decreasing
Remain constant
May increase/decrease
The unit of dynamic viscosity in S.I. units is
N-m/s2
N-s/m2
Poise
Stoke
A compound pipe of diameter d1, d2 and d3 having lengths l1, l2 and l3 is to be replaced by an equivalent pipe of uniform diameter d and of the same length (l) as that of the compound pipe. The size of the equivalent pipe is given by
l/d² = (l₁/d₁²) + (l₂/d₂²) + (l₃/d₃²)
l/d³ = (l₁/d₁³) + (l₂/d₂³) + (l₃/d₃³)
l/d⁴ = (l₁/d₁⁴) + (l₂/d₂⁴) + (l₃/d₃⁴)
l/d⁵ = (l₁/d₁⁵) + (l₂/d₂⁵) + (l₃/d₃⁵)
For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
The loss of head at entrance in a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
The factional resistance of a pipe varies approximately with __________ of the liquid.
Pressure
Velocity
Square of velocity
Cube of velocity
The dynamic viscosity of gases __________ with rise in temperature.
Remain unaffected
Increases
Decreases
None of these
When a liquid is flowing through a pipe, the velocity of the liquid is
Maximum at the centre and minimum near the walls
Minimum at the centre and maximum near the walls
Zero at the centre and maximum near the walls
Maximum at the centre and zero near the walls
The upper surface of a weir over which water flows is known is
Crest
Nappy
Sill
Weir top
Flow of water in a pipe about 3 metres in diameter can be measured by
Orifice plate
Venturimeter
Rotameter
Pitot tube
Surface tension has the units of
Newton-sec/m
Newton-m/sec
Newton/m
Newton
The pressure measured with the help of a pressure gauge is called
Atmospheric pressure
Gauge pressure
Absolute pressure
Mean pressure
If the coefficient of discharge is 0.6, then the discharge over a right angled notch is
0.417 H5/2
1.417 H5/2
4.171 H5/2
7.141 H5/2