Enginieering and math question!!!! help!!!?

Question

A commonly used rule of thumb is that the average velocity in a pipe should be about 1 m/s or less for "thin" fluids(viscosity about water). If a pipe needs to deliver 6,000 m^3 of water per day, what diameter is required to sastify the 1 m/s rule?

Answer 1

The bark is worst than the bite here, but you have to do some conversions. The volume per SECOND is 6000 m^3/day divided by 86400 seconds/day or 0.0694 m^3/sec. If we want a velocity of 1 m/s, the pipe cross-sectional area ( V=av) is .0694=a(1) or a=0.0694 m^2. Now, find the diameter corresponding to a circular area = a. I think it is about 0.3 m.