Maximum flow velocity for laminar flow in a pipe

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Homework Statement



Q) Water (p = 998 kg/m^3
, n = 1.0*10^-3 Pa.s at 20C) at 20C flows through a pipe of
diameter 50.0 mm. What is the maximum average flow velocity if the flow is
guaranteed to be laminar? Give your answer in mm/s.

Homework Equations



Reynolds number=(pvd)/n

The Attempt at a Solution


I am absolutely stumped on this last question for my assignment, I have no idea what to or how to calculate the flow from just these given constants.
 
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You're given everything you need for the equation, except for the "soft" values Reynolds numbers that are a result of laminar flow. Most agree on the following:

for circular pipe flow only

laminar: Re < 2000
transitional: 2000 < Re < 4000
turbulent: Re > 4000

So, pick a Re that you think will "guarantee" laminar flow, plug n chug.

Hope I didn't just give it away too easily, but the values of Re were the only thing that you were missing.