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491.

A pressure rise of 500 kPa is needed across a pump in a pipe transporting 0.2 m2/s of water. If the pump is 85% efficient, the power needed, in kW, would be

A.	118	B.	100
C.	85	D.	65
E.	60

492.

The shear stress in a turbulent pipe flow

A.	Varis parabolically with radius	B.	Varis according to the 1/7 the power law
C.	is zero at the centre and increases as linearly to the wall	D.	is zero at the wall and increase linearly to the centre

493.

The viscosity of a fluid varies with

A.	temperature	B.	temperature and pressure
C.	pressure	D.	temperature, pressure and density
E.	density

494.

In an isothermal atmosphere the pressure

A.	is constant with elevation	B.	decreases linearly with elevation
C.	decreases exponentially with elevation	D.	decreases near the surface but approaches a constant value
E.	cannot be related to elevation

495.

The pressure gradient (?p/?x) in a developed turbulent flow in a horizontal pipe

A.	is constant	B.	varies linearly with axial distance
C.	is zero	D.	decreases exponentially
E.	varies directly with the average velocity

496.

The pressure force, in Newtons, on the 15 cm-dia, head light of an automobile travelling at 25 m/s is

A.	10.4	B.	6.8
C.	5.6	D.	4.8
E.	3.2

497.

The pressure inside a 4 cm dia hose is 700 kPa. If the water exits through 1 2 cm dia. Nozzle what velocity in m/s can be expected inside the hose?

A.	20.4	B.	16.3
C.	12.4	D.	10.5
E.	9.7

498.

Water enters a turbine at 900 kPa with negligible velocity. What maximum speed, in m/s, can it reach before it enters the turbine rotor?

A.	52	B.	47
C.	45	D.	48
E.	28

499.

Total drag on a body is the sum of

A.	pressure drag and velocity drag	B.	friction drag and velocity drag
C.	friction drag and pressure drag	D.	pressure drag, velocity drag and friction drag

500.

Mouthpieces are used to measure

A.	velocity	B.	frictionless
C.	pressure	D.	viscosity
E.	rate of flow