A. Decreases
B. Increases
C. Remains unaltered
D. Can either increase or decrease; depends on other factors
Related Mcqs:
- The net positive suction head (NPSH) of a centrifugal pump is defined as the sum of the velocity head and the pressure head at the_________________?
A. Discharge
B. Suction
C. Suction minus vapor pressure of the liquid at suction temperature
D. Discharge minus vapor pressure of the liquid at the discharge temperature - Net positive suction head (NPSH) of a centrifugal pump must be____________________?
A. Greater than the vapour pressure of the liquid
B. Less than the vapour pressure of the liquid
C. Equal to the vapour pressure of the liquid
D. Less than barometric pressure - A centrifugal pump is used to pump water through a horizontal distance of 150 m, and then raised to an overhead tank 10 m above. The pipe is smooth with an I.D of 50 mm. What head (m of water) must the pump generate at its exit E. to deliver water at a flow rate of 0.001 m3/s? The Fanning friction factor, f is 0.0062 ?
A. 10 m
B. 11 m
C. 11.8 m
D. 30 m - A centrifugal pump used to pump water is used to pump an oil with specific gravity of 0.8 at the same rate. The power consumption will now_________________?
A. Increase
B. Decrease
C. Remain same
D. Data insufficient to predict - A centrifugal pump designed to pump water is employed to pump a more viscous oil. In the later case, the pump_________________?
A. Develops a lower head
B. Capacity is reduced
C. Requires more power
D. All A., B. and C. - A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, the new discharge will be __________ litres/minute ?
A. 500
B. 200
C. 1000
D. 750 - A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, then the new head will be ______________ metres?
A. 2
B. 4
C. 8
D. 5.5 - A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, the power consumed now will be _____________ hp?
A. 0.5
B. 2
C. 4
D. 1 - Low specific speed of a pump implies that, it is a/an ______________ pump?
A. Axial flow
B. Centrifugal
C. Mixed flow
D. None of these - Specific speed of a centrifugal pump relates it with another pump having the___________________?
A. Dynamic similarity
B. Same efficiency
C. Same speed
D. Geometrical similarity