Calculating Water Viscosity from Flow Rate

[JosephL]

Homework Statement

Find the viscosity of water given that;

flow rate (cm^3 s^{-1}) = 2.0
height from tube (m) = 0.1

l (m) = 0.2
r (mm) = 1
\rho = 1000
g = 9.81

Using the equations;

x = \frac{Flow Rate}{Height}

x = \frac{\pi \rho gr^4}{8l\eta}

The Attempt at a Solution

Okay so first, and the most important bit I don't know if I'm doing right I convert the flow rate from cm^3 s^{-1} to m^3 s^{-1} by multiplying by 10^{-6}

So flow rate is now 2 * 10^{-6} m^3 s^{-1} ***I don't know if that bit is correct.***

Then x = \frac{2 * 10^{-6}}{0.1} = 2 * 10^{-5}

and 2 * 10^{-5} = \frac{\pi \rho gr^4}{8l\eta}

After re-arranging and substituting I get;

\eta = 9.6*10^{-4}------

If anyone could check my answer it would be greatly appreciated I haven't done physics for so long I've pretty much forgotten everything.

Thanks in advance

 

[joeyar]

I got the exact same answer you got, using your data.