A centrifugal pump has an impeller of 30 cm diameter and runs at 1000 rpm giving best efficiency. It delivered 1.2 m3/minute against a head of 25 m. What is its non-dimensional specific speed (based on flow expressed in l.p.s)? Take \(\sqrt {9.81} = 3.132\); and \(\sqrt {\sqrt {9.81} } = 1.77\)

A centrifugal pump has an impeller of 30 cm diameter and runs at 1000

1.	A centrifugal pump has an impeller of 30 cm diameter and runs at 1000 rpm giving best efficiency. It delivered 1.2 m3/minute against a head of 25 m. What is its non-dimensional specific speed (based on flow expressed in l.p.s)? Take \(\sqrt {9.81} = 3.132\); and \(\sqrt {\sqrt {9.81} } = 1.77\)
A.	55
B.	63
C.	72
D.	80
Answer» D. 80