What pressure difference is required between the ends of a 2.0--long, 1.0--diameter horizontal tube for 40 water to flow through it at an average speed of 4.0 ?

Question

I know we have to find delta P, but i'm stuck on how to do that.
Help would be great

Answer 1

To find delta P, use

(deltaP)=8(pi)(eta)(L*v)/A

Where eta is the coefficient for viscosity. For 40C water, it is .07e-3 Pa*s.