Computes power requirements for a pump :
Power = (9810*SG)*Q*H/E
SG = Specific Gravity of the Liquid (1.0 == water)
Q = Pump discharge (cubic meters per second)
H = Added head (meters)
E = Mechanical efficiency (percent %)
Notes:
Formula in SI units returns value in N-m/sec;
Calculator also returns discharge in liters per minute,
and power values in horsepower and watts