9. Delivery head of a centrifugal pump is
A. directly proportional to N2
B. inversely proportional to N2
C. inversely proportional to N
D. directly proportional to N
9. Delivery head of a centrifugal pump is
A. directly proportional to N2
B. inversely proportional to N2
C. inversely proportional to N
D. directly proportional to N