8. Centrifugal pump is started with its Delivery valve
A.Kept fully closed
B.Kept fully open
C.Irrespective of any position
D.Kept 50% open
9. A centrifugal pump has speed 1000 r.p.m., flow 1200 l.p.m., head 20m, power 5 H.P., if speed is increased to 1500 r.p.m. then new H.P. will be
A.5 H.P.
B.7.5 H.P.
C.11.25 H.P.
D.16.9 H.P.
10. A centrifugal pump has speed 1000 r.p.m., flow 1200 l.p.m., head 20m, power 5 H.P., if speed is increased to 1500 r.p.m. then new flow will be
A.1800 l.p.m.
B.2700 l.p.m.
C.1200 l.p.m.
D.4500 l.p.m.
11. The efficiency of a centrifugal pump is maximum when its blades are
A.Straight
B.Bent forward
C.Bent backward
D.Bent forward first and then backward
12. The power required to drive a centrifugal pump is proportional to
A.Speen (N)
B.N^2
C.N^3
D.1/ N^2
13. For starting an axial flow pump, its delivery valve should be
A.Closed
B.Open
C.Depends on starting condition and flow desired
D.Could be either open or closed
14. If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge, The horse power required will be
A.Same
B.0.75 B.H.P.
C.B.H.P./0.75
D.1.5 B.H.P.
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